55721358 has 96 divisors (see below), whose sum is σ = 156199680. Its totient is φ = 14463360.

The previous prime is 55721329. The next prime is 55721363. The reversal of 55721358 is 85312755.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36678 + ... + 38166.

It is an arithmetic number, because the mean of its divisors is an integer number (1627080).

Almost surely, 2^55721358 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55721358, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78099840).

55721358 is an abundant number, since it is smaller than the sum of its proper divisors (100478322).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55721358 is a wasteful number, since it uses less digits than its factorization.

55721358 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1524 (or 1512 counting only the distinct ones).

The product of its digits is 42000, while the sum is 36.

The square root of 55721358 is about 7464.6740049382. The cubic root of 55721358 is about 381.9506300240.

The spelling of 55721358 in words is "fifty-five million, seven hundred twenty-one thousand, three hundred fifty-eight".