51401251 has 48 divisors (see below), whose sum is σ = 67196160. Its totient is φ = 38776320.

The previous prime is 51401243. The next prime is 51401267. The reversal of 51401251 is 15210415.

It is not a de Polignac number, because 51401251 - 2³ = 51401243 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is not an unprimeable number, because it can be changed into a prime (51401201) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1389205 + ... + 1389241.

It is an arithmetic number, because the mean of its divisors is an integer number (1399920).

Almost surely, 2^51401251 is an apocalyptic number.

51401251 is a deficient number, since it is larger than the sum of its proper divisors (15794909).

51401251 is a wasteful number, since it uses less digits than its factorization.

51401251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 51401251 is about 7169.4665770893. The cubic root of 51401251 is about 371.8129937433.

Adding to 51401251 its reverse (15210415), we get a palindrome (66611666).

The spelling of 51401251 in words is "fifty-one million, four hundred one thousand, two hundred fifty-one".