721871850669 has 4 divisors (see below), whose sum is σ = 962495800896. Its totient is φ = 481247900444.

The previous prime is 721871850659. The next prime is 721871850701. The reversal of 721871850669 is 966058178127.

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 721871850669 - 2²⁵ = 721838296237 is a prime.

It is a super-2 number, since 2×721871850669² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721871850619) 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, 120311975109 + ... + 120311975114.

It is an arithmetic number, because the mean of its divisors is an integer number (240623950224).

Almost surely, 2^721871850669 is an apocalyptic number.

It is an amenable number.

721871850669 is a deficient number, since it is larger than the sum of its proper divisors (240623950227).

721871850669 is a wasteful number, since it uses less digits than its factorization.

721871850669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240623950226.

The product of its (nonzero) digits is 10160640, while the sum is 60.

The spelling of 721871850669 in words is "seven hundred twenty-one billion, eight hundred seventy-one million, eight hundred fifty thousand, six hundred sixty-nine".