55399660 has 12 divisors (see below), whose sum is σ = 116339328. Its totient is φ = 22159856.

The previous prime is 55399639. The next prime is 55399661. The reversal of 55399660 is 6699355.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (55399661) 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, 1384972 + ... + 1385011.

It is an arithmetic number, because the mean of its divisors is an integer number (9694944).

Almost surely, 2^55399660 is an apocalyptic number.

It is an amenable number.

55399660 is an abundant number, since it is smaller than the sum of its proper divisors (60939668).

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

55399660 is a wasteful number, since it uses less digits than its factorization.

55399660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2769992 (or 2769990 counting only the distinct ones).

The product of its (nonzero) digits is 218700, while the sum is 43.

The square root of 55399660 is about 7443.0947864447. The cubic root of 55399660 is about 381.2141680917.

The spelling of 55399660 in words is "fifty-five million, three hundred ninety-nine thousand, six hundred sixty".