156661031 has 2 divisors, whose sum is σ = 156661032. Its totient is φ = 156661030.

The previous prime is 156661019. The next prime is 156661049. The reversal of 156661031 is 130166651.

It is a weak prime.

It is an emirp because it is prime and its reverse (130166651) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-156661031 is a prime.

It is a super-2 number, since 2×156661031² = 49085357267965922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 156660985 and 156661003.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (156661051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78330515 + 78330516.

It is an arithmetic number, because the mean of its divisors is an integer number (78330516).

Almost surely, 2^156661031 is an apocalyptic number.

156661031 is a deficient number, since it is larger than the sum of its proper divisors (1).

156661031 is an equidigital number, since it uses as much as digits as its factorization.

156661031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 156661031 is about 12516.4304416235. The cubic root of 156661031 is about 539.0805466831.

The spelling of 156661031 in words is "one hundred fifty-six million, six hundred sixty-one thousand, thirty-one".