53720729 has 4 divisors (see below), whose sum is σ = 53861376. Its totient is φ = 53580084.

The previous prime is 53720677. The next prime is 53720743. The reversal of 53720729 is 92702735.

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.

It is a cyclic number.

It is not a de Polignac number, because 53720729 - 2⁸ = 53720473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (53720129) 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, 69749 + ... + 70514.

It is an arithmetic number, because the mean of its divisors is an integer number (13465344).

Almost surely, 2^53720729 is an apocalyptic number.

It is an amenable number.

53720729 is a deficient number, since it is larger than the sum of its proper divisors (140647).

53720729 is a wasteful number, since it uses less digits than its factorization.

53720729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140646.

The product of its (nonzero) digits is 26460, while the sum is 35.

The square root of 53720729 is about 7329.4426118225. The cubic root of 53720729 is about 377.3235969517.

The spelling of 53720729 in words is "fifty-three million, seven hundred twenty thousand, seven hundred twenty-nine".