156688121 has 4 divisors (see below), whose sum is σ = 163500672. Its totient is φ = 149875572.

The previous prime is 156688093. The next prime is 156688123. The reversal of 156688121 is 121886651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 156688121 - 2⁶ = 156688057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (156688123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3406241 + ... + 3406286.

It is an arithmetic number, because the mean of its divisors is an integer number (40875168).

Almost surely, 2^156688121 is an apocalyptic number.

It is an amenable number.

156688121 is a deficient number, since it is larger than the sum of its proper divisors (6812551).

156688121 is an equidigital number, since it uses as much as digits as its factorization.

156688121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6812550.

The product of its digits is 23040, while the sum is 38.

The square root of 156688121 is about 12517.5125723923. The cubic root of 156688121 is about 539.1116176951. Note that the first 3 decimals are identical.

The spelling of 156688121 in words is "one hundred fifty-six million, six hundred eighty-eight thousand, one hundred twenty-one".