51421212 has 36 divisors (see below), whose sum is σ = 130213720. Its totient is φ = 17109792.

The previous prime is 51421193. The next prime is 51421213. The reversal of 51421212 is 21212415.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51421213) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28983 + ... + 30705.

Almost surely, 2^51421212 is an apocalyptic number.

It is an amenable number.

51421212 is an abundant number, since it is smaller than the sum of its proper divisors (78792508).

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

51421212 is a wasteful number, since it uses less digits than its factorization.

51421212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2562 (or 2557 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 51421212 is about 7170.8585260065. The cubic root of 51421212 is about 371.8611170770.

Adding to 51421212 its reverse (21212415), we get a palindrome (72633627).

The spelling of 51421212 in words is "fifty-one million, four hundred twenty-one thousand, two hundred twelve".