51645660 has 96 divisors (see below), whose sum is σ = 167069952. Its totient is φ = 11781120.

The previous prime is 51645641. The next prime is 51645661. The reversal of 51645660 is 6654615.

It is a hoax number, since the sum of its digits (33) 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 (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51645661) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 8919 + ... + 13521.

It is an arithmetic number, because the mean of its divisors is an integer number (1740312).

Almost surely, 2^51645660 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51645660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83534976).

51645660 is an abundant number, since it is smaller than the sum of its proper divisors (115424292).

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

51645660 is a wasteful number, since it uses less digits than its factorization.

51645660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4643 (or 4641 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 51645660 is about 7186.4914944638. The cubic root of 51645660 is about 372.4013762297.

The spelling of 51645660 in words is "fifty-one million, six hundred forty-five thousand, six hundred sixty".