31241221 has 16 divisors (see below), whose sum is σ = 35598528. Its totient is φ = 27164800.

The previous prime is 31241179. The next prime is 31241227. The reversal of 31241221 is 12214213.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31241221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31241195 and 31241204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31241227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23250 + ... + 24556.

It is an arithmetic number, because the mean of its divisors is an integer number (2224908).

Almost surely, 2^31241221 is an apocalyptic number.

It is an amenable number.

31241221 is a deficient number, since it is larger than the sum of its proper divisors (4357307).

31241221 is a wasteful number, since it uses less digits than its factorization.

31241221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412.

The product of its digits is 96, while the sum is 16.

The square root of 31241221 is about 5589.3846709633. The cubic root of 31241221 is about 314.9507641195.

Adding to 31241221 its reverse (12214213), we get a palindrome (43455434).

The spelling of 31241221 in words is "thirty-one million, two hundred forty-one thousand, two hundred twenty-one".