51261984 has 60 divisors (see below), whose sum is σ = 150767694. Its totient is φ = 17086464.

The previous prime is 51261979. The next prime is 51261997. The reversal of 51261984 is 48916215.

51261984 is a `hidden beast` number, since 512 + 61 + 9 + 84 = 666.

It can be written as a sum of positive squares in only one way, i.e., 44355600 + 6906384 = 6660^2 + 2628^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 7297 + ... + 12480.

Almost surely, 2^51261984 is an apocalyptic number.

51261984 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

51261984 is an abundant number, since it is smaller than the sum of its proper divisors (99505710).

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

51261984 is a wasteful number, since it uses less digits than its factorization.

51261984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19799 (or 19782 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 51261984 is about 7159.7474815806. The cubic root of 51261984 is about 371.4768922201.

The spelling of 51261984 in words is "fifty-one million, two hundred sixty-one thousand, nine hundred eighty-four".