51205557 has 8 divisors (see below), whose sum is σ = 73525984. Its totient is φ = 31511088.

The previous prime is 51205549. The next prime is 51205577. The reversal of 51205557 is 75550215.

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

It is not a de Polignac number, because 51205557 - 2³ = 51205549 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 (51205577) 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, 656443 + ... + 656520.

It is an arithmetic number, because the mean of its divisors is an integer number (9190748).

Almost surely, 2^51205557 is an apocalyptic number.

It is an amenable number.

51205557 is a deficient number, since it is larger than the sum of its proper divisors (22320427).

51205557 is a wasteful number, since it uses less digits than its factorization.

51205557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1312979.

The product of its (nonzero) digits is 8750, while the sum is 30.

The square root of 51205557 is about 7155.8058246434. The cubic root of 51205557 is about 371.3405402182.

The spelling of 51205557 in words is "fifty-one million, two hundred five thousand, five hundred fifty-seven".