51745440 has 96 divisors (see below), whose sum is σ = 165533760. Its totient is φ = 13584384.

The previous prime is 51745427. The next prime is 51745459. The reversal of 51745440 is 4454715.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 51745398 and 51745407.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31356 + ... + 32964.

It is an arithmetic number, because the mean of its divisors is an integer number (1724310).

Almost surely, 2^51745440 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 51745440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82766880).

51745440 is an abundant number, since it is smaller than the sum of its proper divisors (113788320).

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

51745440 is a wasteful number, since it uses less digits than its factorization.

51745440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1694 (or 1686 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 30.

The square root of 51745440 is about 7193.4303360775. The cubic root of 51745440 is about 372.6410498373.

The spelling of 51745440 in words is "fifty-one million, seven hundred forty-five thousand, four hundred forty".