51505553 has 8 divisors (see below), whose sum is σ = 57558816. Its totient is φ = 45680800.

The previous prime is 51505549. The next prime is 51505603. The reversal of 51505553 is 35550515.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51505553 - 2² = 51505549 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51505543) 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, 56651 + ... + 57552.

It is an arithmetic number, because the mean of its divisors is an integer number (7194852).

Almost surely, 2^51505553 is an apocalyptic number.

It is an amenable number.

51505553 is a deficient number, since it is larger than the sum of its proper divisors (6053263).

51505553 is a wasteful number, since it uses less digits than its factorization.

51505553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114255.

The product of its (nonzero) digits is 9375, while the sum is 29.

The square root of 51505553 is about 7176.7369326178. The cubic root of 51505553 is about 372.0643147173.

The spelling of 51505553 in words is "fifty-one million, five hundred five thousand, five hundred fifty-three".