51643465 has 12 divisors (see below), whose sum is σ = 63180684. Its totient is φ = 40524224.

The previous prime is 51643429. The next prime is 51643481. The reversal of 51643465 is 56434615.

It can be written as a sum of positive squares in 6 ways, for example, as 5035536 + 46607929 = 2244^2 + 6827^2 .

It is not a de Polignac number, because 51643465 - 2²⁵ = 18089033 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51643465.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12207 + ... + 15883.

It is an arithmetic number, because the mean of its divisors is an integer number (5265057).

Almost surely, 2^51643465 is an apocalyptic number.

It is an amenable number.

51643465 is a deficient number, since it is larger than the sum of its proper divisors (11537219).

51643465 is an equidigital number, since it uses as much as digits as its factorization.

51643465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3788 (or 3735 counting only the distinct ones).

The product of its digits is 43200, while the sum is 34.

The square root of 51643465 is about 7186.3387757606. The cubic root of 51643465 is about 372.3961003259.

The spelling of 51643465 in words is "fifty-one million, six hundred forty-three thousand, four hundred sixty-five".