51220800561 has 16 divisors (see below), whose sum is σ = 78072192000. Its totient is φ = 29260985808.

The previous prime is 51220800541. The next prime is 51220800563. The reversal of 51220800561 is 16500802215.

It is not a de Polignac number, because 51220800561 - 2¹⁸ = 51220538417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51220800563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 256461 + ... + 410138.

It is an arithmetic number, because the mean of its divisors is an integer number (4879512000).

Almost surely, 2^51220800561 is an apocalyptic number.

It is an amenable number.

51220800561 is a deficient number, since it is larger than the sum of its proper divisors (26851391439).

51220800561 is a wasteful number, since it uses less digits than its factorization.

51220800561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670268.

The product of its (nonzero) digits is 4800, while the sum is 30.

The spelling of 51220800561 in words is "fifty-one billion, two hundred twenty million, eight hundred thousand, five hundred sixty-one".