51621611 has 4 divisors (see below), whose sum is σ = 51938472. Its totient is φ = 51304752.

The previous prime is 51621593. The next prime is 51621617. The reversal of 51621611 is 11612615.

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 51621611 - 2¹⁴ = 51605227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51621617) 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, 158186 + ... + 158511.

It is an arithmetic number, because the mean of its divisors is an integer number (12984618).

Almost surely, 2^51621611 is an apocalyptic number.

51621611 is a deficient number, since it is larger than the sum of its proper divisors (316861).

51621611 is a wasteful number, since it uses less digits than its factorization.

51621611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316860.

The product of its digits is 360, while the sum is 23.

The square root of 51621611 is about 7184.8180909470. The cubic root of 51621611 is about 372.3435638781.

The spelling of 51621611 in words is "fifty-one million, six hundred twenty-one thousand, six hundred eleven".