1561000511 has 16 divisors (see below), whose sum is σ = 1833721920. Its totient is φ = 1300769280.

The previous prime is 1561000439. The next prime is 1561000531. The reversal of 1561000511 is 1150001651.

It is a cyclic number.

It is not a de Polignac number, because 1561000511 - 2¹⁸ = 1560738367 is a prime.

It is a super-2 number, since 2×1561000511² = 4873445190684522242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561000531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 558305 + ... + 561093.

It is an arithmetic number, because the mean of its divisors is an integer number (114607620).

Almost surely, 2^1561000511 is an apocalyptic number.

1561000511 is a deficient number, since it is larger than the sum of its proper divisors (272721409).

1561000511 is a wasteful number, since it uses less digits than its factorization.

1561000511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4994.

The product of its (nonzero) digits is 150, while the sum is 20.

The square root of 1561000511 is about 39509.4989970766. The cubic root of 1561000511 is about 1160.0258889882.

The spelling of 1561000511 in words is "one billion, five hundred sixty-one million, five hundred eleven", and thus it is an aban number.