51635551 has 4 divisors (see below), whose sum is σ = 56329704. Its totient is φ = 46941400.

The previous prime is 51635539. The next prime is 51635557. The reversal of 51635551 is 15553615.

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

It is not a de Polignac number, because 51635551 - 2⁹ = 51635039 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51635557) 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, 2347060 + ... + 2347081.

It is an arithmetic number, because the mean of its divisors is an integer number (14082426).

Almost surely, 2^51635551 is an apocalyptic number.

51635551 is a deficient number, since it is larger than the sum of its proper divisors (4694153).

51635551 is a wasteful number, since it uses less digits than its factorization.

51635551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4694152.

The product of its digits is 11250, while the sum is 31.

The square root of 51635551 is about 7185.7881265732. The cubic root of 51635551 is about 372.3770769878.

The spelling of 51635551 in words is "fifty-one million, six hundred thirty-five thousand, five hundred fifty-one".