55763721 has 20 divisors (see below), whose sum is σ = 89710852. Its totient is φ = 34315488.

The previous prime is 55763717. The next prime is 55763759. The reversal of 55763721 is 12736755.

It can be written as a sum of positive squares in 2 ways, for example, as 3404025 + 52359696 = 1845^2 + 7236^2 .

It is not a de Polignac number, because 55763721 - 2² = 55763717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55763711) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 25426 + ... + 27531.

Almost surely, 2^55763721 is an apocalyptic number.

It is an amenable number.

55763721 is a deficient number, since it is larger than the sum of its proper divisors (33947131).

55763721 is a wasteful number, since it uses less digits than its factorization.

55763721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52982 (or 52973 counting only the distinct ones).

The product of its digits is 44100, while the sum is 36.

The square root of 55763721 is about 7467.5110311268. The cubic root of 55763721 is about 382.0474000738.

The spelling of 55763721 in words is "fifty-five million, seven hundred sixty-three thousand, seven hundred twenty-one".