51221612 has 24 divisors (see below), whose sum is σ = 102213216. Its totient is φ = 22249728.

The previous prime is 51221593. The next prime is 51221623. The reversal of 51221612 is 21612215.

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, 28088 + ... + 29855.

It is an arithmetic number, because the mean of its divisors is an integer number (4258884).

Almost surely, 2^51221612 is an apocalyptic number.

51221612 is a gapful number since it is divisible by the number (52) formed by its first and last digit.

It is an amenable number.

51221612 is a deficient number, since it is larger than the sum of its proper divisors (50991604).

51221612 is a wasteful number, since it uses less digits than its factorization.

51221612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57977 (or 57975 counting only the distinct ones).

The product of its digits is 240, while the sum is 20.

The square root of 51221612 is about 7156.9275530775. The cubic root of 51221612 is about 371.3793462238.

Adding to 51221612 its reverse (21612215), we get a palindrome (72833827).

The spelling of 51221612 in words is "fifty-one million, two hundred twenty-one thousand, six hundred twelve".