31629421 has 2 divisors, whose sum is σ = 31629422. Its totient is φ = 31629420.

The previous prime is 31629383. The next prime is 31629431. The reversal of 31629421 is 12492613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29975625 + 1653796 = 5475^2 + 1286^2 .

It is a cyclic number.

It is not a de Polignac number, because 31629421 - 2¹¹ = 31627373 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31629421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31629431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15814710 + 15814711.

It is an arithmetic number, because the mean of its divisors is an integer number (15814711).

Almost surely, 2^31629421 is an apocalyptic number.

It is an amenable number.

31629421 is a deficient number, since it is larger than the sum of its proper divisors (1).

31629421 is an equidigital number, since it uses as much as digits as its factorization.

31629421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 28.

The square root of 31629421 is about 5624.0040007098. The cubic root of 31629421 is about 316.2499124602.

The spelling of 31629421 in words is "thirty-one million, six hundred twenty-nine thousand, four hundred twenty-one".