31221001 has 8 divisors (see below), whose sum is σ = 35881920. Its totient is φ = 26610288.

The previous prime is 31220989. The next prime is 31221017. The reversal of 31221001 is 10012213.

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

It is a cyclic number.

It is not a de Polignac number, because 31221001 - 2⁷ = 31220873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31221041) 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, 11206 + ... + 13711.

It is an arithmetic number, because the mean of its divisors is an integer number (4485240).

Almost surely, 2^31221001 is an apocalyptic number.

It is an amenable number.

31221001 is a deficient number, since it is larger than the sum of its proper divisors (4660919).

31221001 is a wasteful number, since it uses less digits than its factorization.

31221001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25103.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 31221001 is about 5587.5755923298. The cubic root of 31221001 is about 314.8828017860.

Adding to 31221001 its reverse (10012213), we get a palindrome (41233214).

The spelling of 31221001 in words is "thirty-one million, two hundred twenty-one thousand, one".