51667440 has 80 divisors (see below), whose sum is σ = 174738816. Its totient is φ = 12524800.

The previous prime is 51667433. The next prime is 51667457. The reversal of 51667440 is 4476615.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

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, 7146 + ... + 12425.

Almost surely, 2^51667440 is an apocalyptic number.

It is an amenable number.

51667440 is an abundant number, since it is smaller than the sum of its proper divisors (123071376).

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

51667440 is a wasteful number, since it uses less digits than its factorization.

51667440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19598 (or 19592 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 51667440 is about 7188.0066777932. The cubic root of 51667440 is about 372.4537185567.

The spelling of 51667440 in words is "fifty-one million, six hundred sixty-seven thousand, four hundred forty".