1556681157 has 6 divisors (see below), whose sum is σ = 2248539462. Its totient is φ = 1037787432.

The previous prime is 1556681129. The next prime is 1556681171. The reversal of 1556681157 is 7511866551.

It is a happy number.

1556681157 is a `hidden beast` number, since 1 + 5 + 566 + 81 + 1 + 5 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 829785636 + 726895521 = 28806^2 + 26961^2 .

It is not a de Polignac number, because 1556681157 - 2¹⁰ = 1556680133 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1556681117) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 86482278 + ... + 86482295.

It is an arithmetic number, because the mean of its divisors is an integer number (374756577).

Almost surely, 2^1556681157 is an apocalyptic number.

It is an amenable number.

1556681157 is a deficient number, since it is larger than the sum of its proper divisors (691858305).

1556681157 is a wasteful number, since it uses less digits than its factorization.

1556681157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172964579 (or 172964576 counting only the distinct ones).

The product of its digits is 252000, while the sum is 45.

The square root of 1556681157 is about 39454.7989096384. The cubic root of 1556681157 is about 1158.9549538145.

The spelling of 1556681157 in words is "one billion, five hundred fifty-six million, six hundred eighty-one thousand, one hundred fifty-seven".