51649872 has 20 divisors (see below), whose sum is σ = 133428960. Its totient is φ = 17216608.

The previous prime is 51649867. The next prime is 51649877. The reversal of 51649872 is 27894615.

It is an interprime number because it is at equal distance from previous prime (51649867) and next prime (51649877).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51649877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537972 + ... + 538067.

It is an arithmetic number, because the mean of its divisors is an integer number (6671448).

Almost surely, 2^51649872 is an apocalyptic number.

It is an amenable number.

51649872 is an abundant number, since it is smaller than the sum of its proper divisors (81779088).

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

51649872 is a wasteful number, since it uses less digits than its factorization.

51649872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1076050 (or 1076044 counting only the distinct ones).

The product of its digits is 120960, while the sum is 42.

The square root of 51649872 is about 7186.7845383036. The cubic root of 51649872 is about 372.4114997778.

The spelling of 51649872 in words is "fifty-one million, six hundred forty-nine thousand, eight hundred seventy-two".