53991329 has 4 divisors (see below), whose sum is σ = 61704384. Its totient is φ = 46278276.

The previous prime is 53991323. The next prime is 53991341. The reversal of 53991329 is 92319935.

It is a happy number.

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 53991329 - 2¹⁶ = 53925793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (53991323) 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, 3856517 + ... + 3856530.

It is an arithmetic number, because the mean of its divisors is an integer number (15426096).

Almost surely, 2^53991329 is an apocalyptic number.

It is an amenable number.

53991329 is a deficient number, since it is larger than the sum of its proper divisors (7713055).

53991329 is an equidigital number, since it uses as much as digits as its factorization.

53991329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7713054.

The product of its digits is 65610, while the sum is 41.

The square root of 53991329 is about 7347.8792178424. The cubic root of 53991329 is about 377.9560828199.

The spelling of 53991329 in words is "fifty-three million, nine hundred ninety-one thousand, three hundred twenty-nine".