1561152020 has 12 divisors (see below), whose sum is σ = 3278419284. Its totient is φ = 624460800.

The previous prime is 1561152017. The next prime is 1561152049. The reversal of 1561152020 is 202511651.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 921972496 + 639179524 = 30364^2 + 25282^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39028781 + ... + 39028820.

It is an arithmetic number, because the mean of its divisors is an integer number (273201607).

Almost surely, 2^1561152020 is an apocalyptic number.

1561152020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1561152020 is an abundant number, since it is smaller than the sum of its proper divisors (1717267264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1561152020 is a wasteful number, since it uses less digits than its factorization.

1561152020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78057610 (or 78057608 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 23.

The square root of 1561152020 is about 39511.4163249054. The cubic root of 1561152020 is about 1160.0634180548.

Adding to 1561152020 its reverse (202511651), we get a palindrome (1763663671).

The spelling of 1561152020 in words is "one billion, five hundred sixty-one million, one hundred fifty-two thousand, twenty".