51376644 has 72 divisors (see below), whose sum is σ = 142859808. Its totient is φ = 15438720.

The previous prime is 51376631. The next prime is 51376667. The reversal of 51376644 is 44667315.

It is a happy number.

51376644 is a `hidden beast` number, since 5 + 1 + 3 + 7 + 6 + 644 = 666.

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 = 51376599 and 51376608.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53779 + ... + 54725.

It is an arithmetic number, because the mean of its divisors is an integer number (1984164).

Almost surely, 2^51376644 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 51376644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71429904).

51376644 is an abundant number, since it is smaller than the sum of its proper divisors (91483164).

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

51376644 is a wasteful number, since it uses less digits than its factorization.

51376644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105 (or 1100 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 51376644 is about 7167.7502746678. The cubic root of 51376644 is about 371.7536523685.

It can be divided in two parts, 5137 and 6644, that added together give a triangular number (11781 = T₁₅₃).

The spelling of 51376644 in words is "fifty-one million, three hundred seventy-six thousand, six hundred forty-four".