16631401 has 2 divisors, whose sum is σ = 16631402. Its totient is φ = 16631400.

The previous prime is 16631399. The next prime is 16631429. The reversal of 16631401 is 10413661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9211225 + 7420176 = 3035^2 + 2724^2 .

It is an emirp because it is prime and its reverse (10413661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16631401 - 2¹ = 16631399 is a prime.

Together with 16631399, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16631501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8315700 + 8315701.

It is an arithmetic number, because the mean of its divisors is an integer number (8315701).

Almost surely, 2^16631401 is an apocalyptic number.

It is an amenable number.

16631401 is a deficient number, since it is larger than the sum of its proper divisors (1).

16631401 is an equidigital number, since it uses as much as digits as its factorization.

16631401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 16631401 is about 4078.1614730170. The cubic root of 16631401 is about 255.2561874904.

The spelling of 16631401 in words is "sixteen million, six hundred thirty-one thousand, four hundred one".