55720331 has 8 divisors (see below), whose sum is σ = 59760720. Its totient is φ = 51790752.

The previous prime is 55720309. The next prime is 55720337. The reversal of 55720331 is 13302755.

55720331 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-55720331 is a prime.

It is a super-2 number, since 2×55720331² = 6209510573499122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55720331.

It is not an unprimeable number, because it can be changed into a prime (55720337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26660 + ... + 28673.

It is an arithmetic number, because the mean of its divisors is an integer number (7470090).

Almost surely, 2^55720331 is an apocalyptic number.

55720331 is a deficient number, since it is larger than the sum of its proper divisors (4040389).

55720331 is a wasteful number, since it uses less digits than its factorization.

55720331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55405.

The product of its (nonzero) digits is 3150, while the sum is 26.

The square root of 55720331 is about 7464.6052139413. The cubic root of 55720331 is about 381.9482834330.

The spelling of 55720331 in words is "fifty-five million, seven hundred twenty thousand, three hundred thirty-one".