208693631 has 2 divisors, whose sum is σ = 208693632. Its totient is φ = 208693630.

The previous prime is 208693621. The next prime is 208693669. The reversal of 208693631 is 136396802.

It is an a-pointer prime, because the next prime (208693669) can be obtained adding 208693631 to its sum of digits (38).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208693631 is a prime.

It is a super-2 number, since 2×208693631² = 87106063239928322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208693621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104346815 + 104346816.

It is an arithmetic number, because the mean of its divisors is an integer number (104346816).

Almost surely, 2^208693631 is an apocalyptic number.

208693631 is a deficient number, since it is larger than the sum of its proper divisors (1).

208693631 is an equidigital number, since it uses as much as digits as its factorization.

208693631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 208693631 is about 14446.2324154085. The cubic root of 208693631 is about 593.1570980256.

The spelling of 208693631 in words is "two hundred eight million, six hundred ninety-three thousand, six hundred thirty-one".