55207720 has 32 divisors (see below), whose sum is σ = 125388000. Its totient is φ = 21875008.

The previous prime is 55207709. The next prime is 55207727. The reversal of 55207720 is 2770255.

It is not an unprimeable number, because it can be changed into a prime (55207727) 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, 2170 + ... + 10729.

It is an arithmetic number, because the mean of its divisors is an integer number (3918375).

Almost surely, 2^55207720 is an apocalyptic number.

It is an amenable number.

55207720 is an abundant number, since it is smaller than the sum of its proper divisors (70180280).

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

55207720 is a wasteful number, since it uses less digits than its factorization.

55207720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13017 (or 13013 counting only the distinct ones).

The product of its (nonzero) digits is 4900, while the sum is 28.

The square root of 55207720 is about 7430.1897687744. The cubic root of 55207720 is about 380.7734017684.

Adding to 55207720 its reverse (2770255), we get a palindrome (57977975).

The spelling of 55207720 in words is "fifty-five million, two hundred seven thousand, seven hundred twenty".