155921404 has 24 divisors (see below), whose sum is σ = 281621648. Its totient is φ = 75479040.

The previous prime is 155921383. The next prime is 155921407. The reversal of 155921404 is 404129551.

It is a super-2 number, since 2×155921404² = 48622968450662432, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155921407) 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, 28732 + ... + 33724.

Almost surely, 2^155921404 is an apocalyptic number.

It is an amenable number.

155921404 is a deficient number, since it is larger than the sum of its proper divisors (125700244).

155921404 is a wasteful number, since it uses less digits than its factorization.

155921404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5245 (or 5243 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 155921404 is about 12486.8492423029. The cubic root of 155921404 is about 538.2308402571.

The spelling of 155921404 in words is "one hundred fifty-five million, nine hundred twenty-one thousand, four hundred four".