51721852 has 72 divisors (see below), whose sum is σ = 115831296. Its totient is φ = 20022912.

The previous prime is 51721847. The next prime is 51721861. The reversal of 51721852 is 25812715.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 134853 + ... + 135235.

It is an arithmetic number, because the mean of its divisors is an integer number (1608768).

Almost surely, 2^51721852 is an apocalyptic number.

51721852 is a gapful number since it is divisible by the number (52) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51721852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57915648).

51721852 is an abundant number, since it is smaller than the sum of its proper divisors (64109444).

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

51721852 is a wasteful number, since it uses less digits than its factorization.

51721852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 467 (or 458 counting only the distinct ones).

The product of its digits is 5600, while the sum is 31.

The square root of 51721852 is about 7191.7905976189. The cubic root of 51721852 is about 372.5844188051.

The spelling of 51721852 in words is "fifty-one million, seven hundred twenty-one thousand, eight hundred fifty-two".