35631721 has 2 divisors, whose sum is σ = 35631722. Its totient is φ = 35631720.

The previous prime is 35631719. The next prime is 35631727. The reversal of 35631721 is 12713653.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35271721 + 360000 = 5939^2 + 600^2 .

It is a cyclic number.

It is not a de Polignac number, because 35631721 - 2¹ = 35631719 is a prime.

Together with 35631719, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 35631721.

It is not a weakly prime, because it can be changed into another prime (35631727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17815860 + 17815861.

It is an arithmetic number, because the mean of its divisors is an integer number (17815861).

Almost surely, 2^35631721 is an apocalyptic number.

It is an amenable number.

35631721 is a deficient number, since it is larger than the sum of its proper divisors (1).

35631721 is an equidigital number, since it uses as much as digits as its factorization.

35631721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3780, while the sum is 28.

The square root of 35631721 is about 5969.2311900277. The cubic root of 35631721 is about 329.0629092908.

The spelling of 35631721 in words is "thirty-five million, six hundred thirty-one thousand, seven hundred twenty-one".