51989904 has 80 divisors (see below), whose sum is σ = 150407040. Its totient is φ = 17193600.

The previous prime is 51989869. The next prime is 51989933. The reversal of 51989904 is 40998915.

It is a self number, because there is not a number n which added to its sum of digits gives 51989904.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64834 + ... + 65630.

It is an arithmetic number, because the mean of its divisors is an integer number (1880088).

Almost surely, 2^51989904 is an apocalyptic number.

51989904 is a gapful number since it is divisible by the number (54) 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 51989904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75203520).

51989904 is an abundant number, since it is smaller than the sum of its proper divisors (98417136).

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

51989904 is a wasteful number, since it uses less digits than its factorization.

51989904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 965 (or 953 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 51989904 is about 7210.4024852986. The cubic root of 51989904 is about 373.2269580717.

The spelling of 51989904 in words is "fifty-one million, nine hundred eighty-nine thousand, nine hundred four".