51679440 has 60 divisors (see below), whose sum is σ = 173559204. Its totient is φ = 13780992.

The previous prime is 51679423. The next prime is 51679447. The reversal of 51679440 is 4497615.

It can be written as a sum of positive squares in 2 ways, for example, as 26998416 + 24681024 = 5196^2 + 4968^2 .

It is a tau number, because it is divible by the number of its divisors (60).

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

It is a junction number, because it is equal to n+sod(n) for n = 51679395 and 51679404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51679447) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35169 + ... + 36608.

Almost surely, 2^51679440 is an apocalyptic number.

It is an amenable number.

51679440 is an abundant number, since it is smaller than the sum of its proper divisors (121879764).

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

51679440 is a wasteful number, since it uses less digits than its factorization.

51679440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71796 (or 71787 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 51679440 is about 7188.8413530972. The cubic root of 51679440 is about 372.4825510197.

The spelling of 51679440 in words is "fifty-one million, six hundred seventy-nine thousand, four hundred forty".