155979771 has 8 divisors (see below), whose sum is σ = 208541184. Its totient is φ = 103702440.

The previous prime is 155979751. The next prime is 155979781. The reversal of 155979771 is 177979551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 155979771 - 2²² = 151785467 is a prime.

It is a super-2 number, since 2×155979771² = 48659377922424882, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (155979701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69735 + ... + 71936.

It is an arithmetic number, because the mean of its divisors is an integer number (26067648).

Almost surely, 2^155979771 is an apocalyptic number.

155979771 is a deficient number, since it is larger than the sum of its proper divisors (52561413).

155979771 is a wasteful number, since it uses less digits than its factorization.

155979771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142041.

The product of its digits is 694575, while the sum is 51.

The square root of 155979771 is about 12489.1861624367. The cubic root of 155979771 is about 538.2979916114.

The spelling of 155979771 in words is "one hundred fifty-five million, nine hundred seventy-nine thousand, seven hundred seventy-one".