31221420999 has 8 divisors (see below), whose sum is σ = 41679146112. Its totient is φ = 20788988280.

The previous prime is 31221420983. The next prime is 31221421013. The reversal of 31221420999 is 99902412213.

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

It is not a de Polignac number, because 31221420999 - 2⁴ = 31221420983 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31221420999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31221420929) 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, 6320217 + ... + 6325154.

It is an arithmetic number, because the mean of its divisors is an integer number (5209893264).

Almost surely, 2^31221420999 is an apocalyptic number.

31221420999 is a deficient number, since it is larger than the sum of its proper divisors (10457725113).

31221420999 is a wasteful number, since it uses less digits than its factorization.

31221420999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12646197.

The product of its (nonzero) digits is 69984, while the sum is 42.

The spelling of 31221420999 in words is "thirty-one billion, two hundred twenty-one million, four hundred twenty thousand, nine hundred ninety-nine".