31331132220221 has 8 divisors (see below), whose sum is σ = 32993077692000. Its totient is φ = 29670480599760.

The previous prime is 31331132220209. The next prime is 31331132220251. The reversal of 31331132220221 is 12202223113313.

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-31331132220221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31331132220251) 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, 323413115 + ... + 323509976.

It is an arithmetic number, because the mean of its divisors is an integer number (4124134711500).

Almost surely, 2^{31331132220221} is an apocalyptic number.

It is an amenable number.

31331132220221 is a deficient number, since it is larger than the sum of its proper divisors (1661945471779).

31331132220221 is a wasteful number, since it uses less digits than its factorization.

31331132220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 646925659.

The product of its (nonzero) digits is 2592, while the sum is 26.

Adding to 31331132220221 its reverse (12202223113313), we get a palindrome (43533355333534).

The spelling of 31331132220221 in words is "thirty-one trillion, three hundred thirty-one billion, one hundred thirty-two million, two hundred twenty thousand, two hundred twenty-one".