53872170387221 has 4 divisors (see below), whose sum is σ = 53872219531200. Its totient is φ = 53872121243244.

The previous prime is 53872170387107. The next prime is 53872170387247. The reversal of 53872170387221 is 12278307127835.

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 a de Polignac number, because none of the positive numbers 2^k-53872170387221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53872170380221) 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, 22889261 + ... + 25132898.

It is an arithmetic number, because the mean of its divisors is an integer number (13468054882800).

Almost surely, 2^{53872170387221} is an apocalyptic number.

It is an amenable number.

53872170387221 is a deficient number, since it is larger than the sum of its proper divisors (49143979).

53872170387221 is a wasteful number, since it uses less digits than its factorization.

53872170387221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49143978.

The product of its (nonzero) digits is 7902720, while the sum is 56.

The spelling of 53872170387221 in words is "fifty-three trillion, eight hundred seventy-two billion, one hundred seventy million, three hundred eighty-seven thousand, two hundred twenty-one".