156646120621 has 4 divisors (see below), whose sum is σ = 156824737372. Its totient is φ = 156467503872.

The previous prime is 156646120613. The next prime is 156646120691. The reversal of 156646120621 is 126021646651.

156646120621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 126021646651 = 1361 ⋅92594891.

It can be written as a sum of positive squares in 2 ways, for example, as 107199927396 + 49446193225 = 327414^2 + 222365^2 .

It is a cyclic number.

It is not a de Polignac number, because 156646120621 - 2³ = 156646120613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (156646120691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89307060 + ... + 89308813.

It is an arithmetic number, because the mean of its divisors is an integer number (39206184343).

Almost surely, 2^156646120621 is an apocalyptic number.

It is an amenable number.

156646120621 is a deficient number, since it is larger than the sum of its proper divisors (178616751).

156646120621 is an equidigital number, since it uses as much as digits as its factorization.

156646120621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178616750.

The product of its (nonzero) digits is 103680, while the sum is 40.

The spelling of 156646120621 in words is "one hundred fifty-six billion, six hundred forty-six million, one hundred twenty thousand, six hundred twenty-one".