1561606101 has 16 divisors (see below), whose sum is σ = 2523808320. Its totient is φ = 946427760.

The previous prime is 1561606087. The next prime is 1561606129. The reversal of 1561606101 is 1016061651.

1561606101 is a `hidden beast` number, since 1 + 56 + 1 + 606 + 1 + 0 + 1 = 666.

It is not a de Polignac number, because 1561606101 - 2⁵ = 1561606069 is a prime.

It is a super-2 number, since 2×1561606101² = 4877227229360844402, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561606301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2628670 + ... + 2629263.

It is an arithmetic number, because the mean of its divisors is an integer number (157738020).

Almost surely, 2^1561606101 is an apocalyptic number.

1561606101 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1561606101 is a deficient number, since it is larger than the sum of its proper divisors (962202219).

1561606101 is a wasteful number, since it uses less digits than its factorization.

1561606101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5257953 (or 5257947 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 1561606101 is about 39517.1621071149. The cubic root of 1561606101 is about 1160.1758802380.

Adding to 1561606101 its reverse (1016061651), we get a palindrome (2577667752).

It can be divided in two parts, 156160 and 6101, that added together give a palindrome (162261).

The spelling of 1561606101 in words is "one billion, five hundred sixty-one million, six hundred six thousand, one hundred one".