53309981 has 8 divisors (see below), whose sum is σ = 55476960. Its totient is φ = 51185232.

The previous prime is 53309969. The next prime is 53310001. The reversal of 53309981 is 18990335.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-53309981 is a prime.

It is a super-2 number, since 2×53309981² = 5683908148440722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53309951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7970 + ... + 13043.

It is an arithmetic number, because the mean of its divisors is an integer number (6934620).

Almost surely, 2^53309981 is an apocalyptic number.

It is an amenable number.

53309981 is a deficient number, since it is larger than the sum of its proper divisors (2166979).

53309981 is a wasteful number, since it uses less digits than its factorization.

53309981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21115.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 53309981 is about 7301.3684333829. The cubic root of 53309981 is about 376.3594650645.

The spelling of 53309981 in words is "fifty-three million, three hundred nine thousand, nine hundred eighty-one".