51321633 has 16 divisors (see below), whose sum is σ = 75423936. Its totient is φ = 30781440.

The previous prime is 51321629. The next prime is 51321637. The reversal of 51321633 is 33612315.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51321629) and next prime (51321637).

It is not a de Polignac number, because 51321633 - 2² = 51321629 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51321637) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4816 + ... + 11217.

It is an arithmetic number, because the mean of its divisors is an integer number (4713996).

Almost surely, 2^51321633 is an apocalyptic number.

It is an amenable number.

51321633 is a deficient number, since it is larger than the sum of its proper divisors (24102303).

51321633 is a wasteful number, since it uses less digits than its factorization.

51321633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16144.

The product of its digits is 1620, while the sum is 24.

The square root of 51321633 is about 7163.9118503790. The cubic root of 51321633 is about 371.6209212155.

Adding to 51321633 its reverse (33612315), we get a palindrome (84933948).

The spelling of 51321633 in words is "fifty-one million, three hundred twenty-one thousand, six hundred thirty-three".