56728407 has 4 divisors (see below), whose sum is σ = 75637880. Its totient is φ = 37818936.

The previous prime is 56728403. The next prime is 56728417. The reversal of 56728407 is 70482765.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 56728407 - 2² = 56728403 is a prime.

It is a super-2 number, since 2×56728407² = 6436224321515298, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56728403) 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, 9454732 + ... + 9454737.

It is an arithmetic number, because the mean of its divisors is an integer number (18909470).

Almost surely, 2^56728407 is an apocalyptic number.

56728407 is a deficient number, since it is larger than the sum of its proper divisors (18909473).

56728407 is a wasteful number, since it uses less digits than its factorization.

56728407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18909472.

The product of its (nonzero) digits is 94080, while the sum is 39.

The square root of 56728407 is about 7531.8262725583. The cubic root of 56728407 is about 384.2378964785.

The spelling of 56728407 in words is "fifty-six million, seven hundred twenty-eight thousand, four hundred seven".