157655809 has 4 divisors (see below), whose sum is σ = 157848660. Its totient is φ = 157462960.

The previous prime is 157655791. The next prime is 157655821. The reversal of 157655809 is 908556751.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 908556751 = 8597 ⋅105683.

It can be written as a sum of positive squares in 2 ways, for example, as 37271025 + 120384784 = 6105^2 + 10972^2 .

It is a cyclic number.

It is not a de Polignac number, because 157655809 - 2¹¹ = 157653761 is a prime.

It is a super-2 number, since 2×157655809² = 49710708222888962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157655899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 95194 + ... + 96835.

It is an arithmetic number, because the mean of its divisors is an integer number (39462165).

Almost surely, 2^157655809 is an apocalyptic number.

It is an amenable number.

157655809 is a deficient number, since it is larger than the sum of its proper divisors (192851).

157655809 is an equidigital number, since it uses as much as digits as its factorization.

157655809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192850.

The product of its (nonzero) digits is 378000, while the sum is 46.

The square root of 157655809 is about 12556.1064426836. The cubic root of 157655809 is about 540.2191714346.

The spelling of 157655809 in words is "one hundred fifty-seven million, six hundred fifty-five thousand, eight hundred nine".