51031998 has 16 divisors (see below), whose sum is σ = 113404560. Its totient is φ = 17010648.

The previous prime is 51031979. The next prime is 51031999. The reversal of 51031998 is 89913015.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51031999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 472465 + ... + 472572.

It is an arithmetic number, because the mean of its divisors is an integer number (7087785).

Almost surely, 2^51031998 is an apocalyptic number.

51031998 is an abundant number, since it is smaller than the sum of its proper divisors (62372562).

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

51031998 is a wasteful number, since it uses less digits than its factorization.

51031998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 945048 (or 945042 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 51031998 is about 7143.6683853606. The cubic root of 51031998 is about 370.9205177944.

The spelling of 51031998 in words is "fifty-one million, thirty-one thousand, nine hundred ninety-eight".