51401551 has 4 divisors (see below), whose sum is σ = 51417504. Its totient is φ = 51385600.

The previous prime is 51401533. The next prime is 51401611. The reversal of 51401551 is 15510415.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51401551 - 2⁷ = 51401423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51401521) 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, 1255 + ... + 10216.

It is an arithmetic number, because the mean of its divisors is an integer number (12854376).

Almost surely, 2^51401551 is an apocalyptic number.

51401551 is a deficient number, since it is larger than the sum of its proper divisors (15953).

51401551 is a wasteful number, since it uses less digits than its factorization.

51401551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15952.

The product of its (nonzero) digits is 500, while the sum is 22.

The square root of 51401551 is about 7169.4874991174. The cubic root of 51401551 is about 371.8137170959.

Adding to 51401551 its reverse (15510415), we get a palindrome (66911966).

The spelling of 51401551 in words is "fifty-one million, four hundred one thousand, five hundred fifty-one".