201601631 has 12 divisors (see below), whose sum is σ = 255836520. Its totient is φ = 157091760.

The previous prime is 201601627. The next prime is 201601637. The reversal of 201601631 is 136106102.

It is not a de Polignac number, because 201601631 - 2² = 201601627 is a prime.

It is a super-2 number, since 2×201601631² = 81286435243720322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201601637) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 186476 + ... + 187553.

It is an arithmetic number, because the mean of its divisors is an integer number (21319710).

Almost surely, 2^201601631 is an apocalyptic number.

201601631 is a deficient number, since it is larger than the sum of its proper divisors (54234889).

201601631 is a wasteful number, since it uses less digits than its factorization.

201601631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374054 (or 374047 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 201601631 is about 14198.6489145975. The cubic root of 201601631 is about 586.3604648158.

Adding to 201601631 its reverse (136106102), we get a palindrome (337707733).

The spelling of 201601631 in words is "two hundred one million, six hundred one thousand, six hundred thirty-one".