156668969 has 2 divisors, whose sum is σ = 156668970. Its totient is φ = 156668968.

The previous prime is 156668959. The next prime is 156668971. The reversal of 156668969 is 969866651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120187369 + 36481600 = 10963^2 + 6040^2 .

It is a cyclic number.

It is not a de Polignac number, because 156668969 - 2²⁴ = 139891753 is a prime.

It is a super-2 number, since 2×156668969² = 49090331695045922, which contains 22 as substring.

Together with 156668971, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (156668959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78334484 + 78334485.

It is an arithmetic number, because the mean of its divisors is an integer number (78334485).

Almost surely, 2^156668969 is an apocalyptic number.

It is an amenable number.

156668969 is a deficient number, since it is larger than the sum of its proper divisors (1).

156668969 is an equidigital number, since it uses as much as digits as its factorization.

156668969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4199040, while the sum is 56.

The square root of 156668969 is about 12516.7475407951. The cubic root of 156668969 is about 539.0896515832.

The spelling of 156668969 in words is "one hundred fifty-six million, six hundred sixty-eight thousand, nine hundred sixty-nine".