51345945 has 24 divisors (see below), whose sum is σ = 101714496. Its totient is φ = 23472288.

The previous prime is 51345941. The next prime is 51345953. The reversal of 51345945 is 54954315.

51345945 = 1366² + 1367² + ... + 1392².

It is not a de Polignac number, because 51345945 - 2² = 51345941 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51345941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 81187 + ... + 81816.

It is an arithmetic number, because the mean of its divisors is an integer number (4238104).

Almost surely, 2^51345945 is an apocalyptic number.

It is an amenable number.

51345945 is a deficient number, since it is larger than the sum of its proper divisors (50368551).

51345945 is a wasteful number, since it uses less digits than its factorization.

51345945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163021 (or 163018 counting only the distinct ones).

The product of its digits is 54000, while the sum is 36.

The square root of 51345945 is about 7165.6084877699. The cubic root of 51345945 is about 371.6795931701.

The spelling of 51345945 in words is "fifty-one million, three hundred forty-five thousand, nine hundred forty-five".