55392821 has 4 divisors (see below), whose sum is σ = 60428544. Its totient is φ = 50357100.

The previous prime is 55392793. The next prime is 55392823. The reversal of 55392821 is 12829355.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55392821 - 2¹⁴ = 55376437 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55392823) 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, 2517845 + ... + 2517866.

It is an arithmetic number, because the mean of its divisors is an integer number (15107136).

Almost surely, 2^55392821 is an apocalyptic number.

It is an amenable number.

55392821 is a deficient number, since it is larger than the sum of its proper divisors (5035723).

55392821 is a wasteful number, since it uses less digits than its factorization.

55392821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5035722.

The product of its digits is 21600, while the sum is 35.

The square root of 55392821 is about 7442.6353531528. The cubic root of 55392821 is about 381.1984806851.

The spelling of 55392821 in words is "fifty-five million, three hundred ninety-two thousand, eight hundred twenty-one".