51027921 has 32 divisors (see below), whose sum is σ = 88743680. Its totient is φ = 28366848.

The previous prime is 51027877. The next prime is 51027929. The reversal of 51027921 is 12972015.

It is not a de Polignac number, because 51027921 - 2⁶ = 51027857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51027929) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3345 + ... + 10641.

It is an arithmetic number, because the mean of its divisors is an integer number (2773240).

Almost surely, 2^51027921 is an apocalyptic number.

It is an amenable number.

51027921 is a deficient number, since it is larger than the sum of its proper divisors (37715759).

51027921 is a wasteful number, since it uses less digits than its factorization.

51027921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7350 (or 7344 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 51027921 is about 7143.3830220701. The cubic root of 51027921 is about 370.9106397879.

Adding to 51027921 its reverse (12972015), we get a palindrome (63999936).

The spelling of 51027921 in words is "fifty-one million, twenty-seven thousand, nine hundred twenty-one".