53721639 has 12 divisors (see below), whose sum is σ = 77716600. Its totient is φ = 35759664.

The previous prime is 53721637. The next prime is 53721641. The reversal of 53721639 is 93612735.

It is an interprime number because it is at equal distance from previous prime (53721637) and next prime (53721641).

It is not a de Polignac number, because 53721639 - 2¹ = 53721637 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 (53721637) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2172 + ... + 10590.

Almost surely, 2^53721639 is an apocalyptic number.

53721639 is a deficient number, since it is larger than the sum of its proper divisors (23994961).

53721639 is a wasteful number, since it uses less digits than its factorization.

53721639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9134 (or 9131 counting only the distinct ones).

The product of its digits is 34020, while the sum is 36.

The square root of 53721639 is about 7329.5046899501. The cubic root of 53721639 is about 377.3257274920.

The spelling of 53721639 in words is "fifty-three million, seven hundred twenty-one thousand, six hundred thirty-nine".