53113721 has 4 divisors (see below), whose sum is σ = 55909200. Its totient is φ = 50318244.

The previous prime is 53113679. The next prime is 53113733. The reversal of 53113721 is 12731135.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12731135 = 5 ⋅2546227.

It is a cyclic number.

It is not a de Polignac number, because 53113721 - 2⁶ = 53113657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (53113771) 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, 1397711 + ... + 1397748.

It is an arithmetic number, because the mean of its divisors is an integer number (13977300).

Almost surely, 2^53113721 is an apocalyptic number.

It is an amenable number.

53113721 is a deficient number, since it is larger than the sum of its proper divisors (2795479).

53113721 is a wasteful number, since it uses less digits than its factorization.

53113721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2795478.

The product of its digits is 630, while the sum is 23.

The square root of 53113721 is about 7287.9160944676. The cubic root of 53113721 is about 375.8970429779.

Adding to 53113721 its reverse (12731135), we get a palindrome (65844856).

The spelling of 53113721 in words is "fifty-three million, one hundred thirteen thousand, seven hundred twenty-one".