31610471221 has 32 divisors (see below), whose sum is σ = 37620506880. Its totient is φ = 25987046400.

The previous prime is 31610471197. The next prime is 31610471227. The reversal of 31610471221 is 12217401613.

It is not a de Polignac number, because 31610471221 - 2⁷ = 31610471093 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31610471221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31610471227) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38501991 + ... + 38502811.

It is an arithmetic number, because the mean of its divisors is an integer number (1175640840).

Almost surely, 2^31610471221 is an apocalyptic number.

It is an amenable number.

31610471221 is a deficient number, since it is larger than the sum of its proper divisors (6010035659).

31610471221 is a wasteful number, since it uses less digits than its factorization.

31610471221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1885.

The product of its (nonzero) digits is 2016, while the sum is 28.

Adding to 31610471221 its reverse (12217401613), we get a palindrome (43827872834).

The spelling of 31610471221 in words is "thirty-one billion, six hundred ten million, four hundred seventy-one thousand, two hundred twenty-one".