55213890 has 32 divisors (see below), whose sum is σ = 134196480. Its totient is φ = 14536704.

The previous prime is 55213853. The next prime is 55213897. The reversal of 55213890 is 9831255.

It is not an unprimeable number, because it can be changed into a prime (55213897) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9279 + ... + 14018.

It is an arithmetic number, because the mean of its divisors is an integer number (4193640).

Almost surely, 2^55213890 is an apocalyptic number.

55213890 is an abundant number, since it is smaller than the sum of its proper divisors (78982590).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55213890 is a wasteful number, since it uses less digits than its factorization.

55213890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23386.

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 55213890 is about 7430.6049551837. The cubic root of 55213890 is about 380.7875862844.

The spelling of 55213890 in words is "fifty-five million, two hundred thirteen thousand, eight hundred ninety".