51921330 has 32 divisors (see below), whose sum is σ = 124804800. Its totient is φ = 13824192.

The previous prime is 51921307. The next prime is 51921341. The reversal of 51921330 is 3312915.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 51921330.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31261 + ... + 32879.

It is an arithmetic number, because the mean of its divisors is an integer number (3900150).

Almost surely, 2^51921330 is an apocalyptic number.

51921330 is an abundant number, since it is smaller than the sum of its proper divisors (72883470).

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

51921330 is a wasteful number, since it uses less digits than its factorization.

51921330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2698.

The product of its (nonzero) digits is 810, while the sum is 24.

The square root of 51921330 is about 7205.6457031969. The cubic root of 51921330 is about 373.0627920556.

The spelling of 51921330 in words is "fifty-one million, nine hundred twenty-one thousand, three hundred thirty".