156855002221 has 2 divisors, whose sum is σ = 156855002222. Its totient is φ = 156855002220.

The previous prime is 156855002177. The next prime is 156855002233. The reversal of 156855002221 is 122200558651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153026486596 + 3828515625 = 391186^2 + 61875^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-156855002221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (156855002251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78427501110 + 78427501111.

It is an arithmetic number, because the mean of its divisors is an integer number (78427501111).

Almost surely, 2^156855002221 is an apocalyptic number.

It is an amenable number.

156855002221 is a deficient number, since it is larger than the sum of its proper divisors (1).

156855002221 is an equidigital number, since it uses as much as digits as its factorization.

156855002221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48000, while the sum is 37.

The spelling of 156855002221 in words is "one hundred fifty-six billion, eight hundred fifty-five million, two thousand, two hundred twenty-one".