51561480 has 32 divisors (see below), whose sum is σ = 154684800. Its totient is φ = 13749696.

The previous prime is 51561479. The next prime is 51561511. The reversal of 51561480 is 8416515.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 214720 + ... + 214959.

It is an arithmetic number, because the mean of its divisors is an integer number (4833900).

Almost surely, 2^51561480 is an apocalyptic number.

It is an amenable number.

51561480 is an abundant number, since it is smaller than the sum of its proper divisors (103123320).

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

51561480 is a wasteful number, since it uses less digits than its factorization.

51561480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 429693 (or 429689 counting only the distinct ones).

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

The square root of 51561480 is about 7180.6322841377. The cubic root of 51561480 is about 372.1989339489.

Adding to 51561480 its reverse (8416515), we get a palindrome (59977995).

The spelling of 51561480 in words is "fifty-one million, five hundred sixty-one thousand, four hundred eighty".