51691252 has 6 divisors (see below), whose sum is σ = 90459698. Its totient is φ = 25845624.

The previous prime is 51691243. The next prime is 51691259. The reversal of 51691252 is 25219615.

It can be written as a sum of positive squares in only one way, i.e., 35093776 + 16597476 = 5924^2 + 4074^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51691259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6461403 + ... + 6461410.

Almost surely, 2^51691252 is an apocalyptic number.

It is an amenable number.

51691252 is a deficient number, since it is larger than the sum of its proper divisors (38768446).

51691252 is a wasteful number, since it uses less digits than its factorization.

51691252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12922817 (or 12922815 counting only the distinct ones).

The product of its digits is 5400, while the sum is 31.

The square root of 51691252 is about 7189.6628571860. The cubic root of 51691252 is about 372.5109274154.

The spelling of 51691252 in words is "fifty-one million, six hundred ninety-one thousand, two hundred fifty-two".