55492721 has 16 divisors (see below), whose sum is σ = 60117120. Its totient is φ = 51089280.

The previous prime is 55492667. The next prime is 55492727. The reversal of 55492721 is 12729455.

It is not a de Polignac number, because 55492721 - 2¹⁸ = 55230577 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (55492727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77915 + ... + 78623.

It is an arithmetic number, because the mean of its divisors is an integer number (3757320).

Almost surely, 2^55492721 is an apocalyptic number.

It is an amenable number.

55492721 is a deficient number, since it is larger than the sum of its proper divisors (4624399).

55492721 is a wasteful number, since it uses less digits than its factorization.

55492721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 856.

The product of its digits is 25200, while the sum is 35.

The square root of 55492721 is about 7449.3436623638. The cubic root of 55492721 is about 381.4275046945.

The spelling of 55492721 in words is "fifty-five million, four hundred ninety-two thousand, seven hundred twenty-one".