156706989312991 has 4 divisors (see below), whose sum is σ = 168761373106312. Its totient is φ = 144652605519672.

The previous prime is 156706989312983. The next prime is 156706989313009. The reversal of 156706989312991 is 199213989607651.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 156706989312991 - 2³ = 156706989312983 is a prime.

It is a super-2 number, since 2×156706989312991² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (156706989312941) 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, 6027191896641 + ... + 6027191896666.

It is an arithmetic number, because the mean of its divisors is an integer number (42190343276578).

Almost surely, 2^{156706989312991} is an apocalyptic number.

156706989312991 is a deficient number, since it is larger than the sum of its proper divisors (12054383793321).

156706989312991 is a wasteful number, since it uses less digits than its factorization.

156706989312991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12054383793320.

The product of its (nonzero) digits is 396809280, while the sum is 76.

The spelling of 156706989312991 in words is "one hundred fifty-six trillion, seven hundred six billion, nine hundred eighty-nine million, three hundred twelve thousand, nine hundred ninety-one".