55139990 has 16 divisors (see below), whose sum is σ = 101935152. Its totient is φ = 21459744.

The previous prime is 55139969. The next prime is 55140011. The reversal of 55139990 is 9993155.

It is an interprime number because it is at equal distance from previous prime (55139969) and next prime (55140011).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74144 + ... + 74883.

It is an arithmetic number, because the mean of its divisors is an integer number (6370947).

Almost surely, 2^55139990 is an apocalyptic number.

55139990 is a deficient number, since it is larger than the sum of its proper divisors (46795162).

55139990 is a wasteful number, since it uses less digits than its factorization.

55139990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149071.

The product of its (nonzero) digits is 54675, while the sum is 41.

The square root of 55139990 is about 7425.6306129513. The cubic root of 55139990 is about 380.6176244231.

The spelling of 55139990 in words is "fifty-five million, one hundred thirty-nine thousand, nine hundred ninety".