55521639 has 8 divisors (see below), whose sum is σ = 82254320. Its totient is φ = 37014408.

The previous prime is 55521611. The next prime is 55521649. The reversal of 55521639 is 93612555.

It is not a de Polignac number, because 55521639 - 2⁵ = 55521607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55521649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1028152 + ... + 1028205.

It is an arithmetic number, because the mean of its divisors is an integer number (10281790).

Almost surely, 2^55521639 is an apocalyptic number.

55521639 is a deficient number, since it is larger than the sum of its proper divisors (26732681).

55521639 is a wasteful number, since it uses less digits than its factorization.

55521639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2056366 (or 2056360 counting only the distinct ones).

The product of its digits is 40500, while the sum is 36.

The square root of 55521639 is about 7451.2843859297. The cubic root of 55521639 is about 381.4937488490.

The spelling of 55521639 in words is "fifty-five million, five hundred twenty-one thousand, six hundred thirty-nine".