54661921 has 4 divisors (see below), whose sum is σ = 55693332. Its totient is φ = 53630512.

The previous prime is 54661909. The next prime is 54661949. The reversal of 54661921 is 12916645.

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

It can be written as a sum of positive squares in 2 ways, for example, as 45751696 + 8910225 = 6764^2 + 2985^2 .

It is a cyclic number.

It is not a de Polignac number, because 54661921 - 2¹⁵ = 54629153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (54661951) 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, 515626 + ... + 515731.

It is an arithmetic number, because the mean of its divisors is an integer number (13923333).

Almost surely, 2^54661921 is an apocalyptic number.

It is an amenable number.

54661921 is a deficient number, since it is larger than the sum of its proper divisors (1031411).

54661921 is a wasteful number, since it uses less digits than its factorization.

54661921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1031410.

The product of its digits is 12960, while the sum is 34.

The square root of 54661921 is about 7393.3700705429. The cubic root of 54661921 is about 379.5144328959.

The spelling of 54661921 in words is "fifty-four million, six hundred sixty-one thousand, nine hundred twenty-one".