31528613 has 2 divisors, whose sum is σ = 31528614. Its totient is φ = 31528612.

The previous prime is 31528579. The next prime is 31528621. The reversal of 31528613 is 31682513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22486564 + 9042049 = 4742^2 + 3007^2 .

It is an emirp because it is prime and its reverse (31682513) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31528613 - 2¹² = 31524517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31528633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15764306 + 15764307.

It is an arithmetic number, because the mean of its divisors is an integer number (15764307).

Almost surely, 2^31528613 is an apocalyptic number.

It is an amenable number.

31528613 is a deficient number, since it is larger than the sum of its proper divisors (1).

31528613 is an equidigital number, since it uses as much as digits as its factorization.

31528613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 29.

The square root of 31528613 is about 5615.0345502054. The cubic root of 31528613 is about 315.9135752811.

The spelling of 31528613 in words is "thirty-one million, five hundred twenty-eight thousand, six hundred thirteen".