31242661 has 2 divisors, whose sum is σ = 31242662. Its totient is φ = 31242660.

The previous prime is 31242643. The next prime is 31242677. The reversal of 31242661 is 16624213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17589636 + 13653025 = 4194^2 + 3695^2 .

It is a cyclic number.

It is not a de Polignac number, because 31242661 - 2⁹ = 31242149 is a prime.

It is a super-2 number, since 2×31242661² = 1952207732721842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31242641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15621330 + 15621331.

It is an arithmetic number, because the mean of its divisors is an integer number (15621331).

Almost surely, 2^31242661 is an apocalyptic number.

It is an amenable number.

31242661 is a deficient number, since it is larger than the sum of its proper divisors (1).

31242661 is an equidigital number, since it uses as much as digits as its factorization.

31242661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 25.

The square root of 31242661 is about 5589.5134850897. The cubic root of 31242661 is about 314.9556030483.

Adding to 31242661 its reverse (16624213), we get a palindrome (47866874).

The spelling of 31242661 in words is "thirty-one million, two hundred forty-two thousand, six hundred sixty-one".