1601631 has 12 divisors (see below), whose sum is σ = 2325960. Its totient is φ = 1062000.

The previous prime is 1601629. The next prime is 1601647. The reversal of 1601631 is 1361061.

1601631 is a `hidden beast` number, since 1 + 601 + 63 + 1 = 666.

It is not a de Polignac number, because 1601631 - 2¹ = 1601629 is a prime.

It is a super-2 number, since 2×1601631² = 5130443720322, which contains 22 as substring.

1601631 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1905 + ... + 2613.

It is an arithmetic number, because the mean of its divisors is an integer number (193830).

2^1601631 is an apocalyptic number.

1601631 is a deficient number, since it is larger than the sum of its proper divisors (724329).

1601631 is a wasteful number, since it uses less digits than its factorization.

1601631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 966 (or 963 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 1601631 is about 1265.5556092089. Note that the first 3 decimals coincide. The cubic root of 1601631 is about 117.0004383065. Note that the first 3 decimals are identical.

Subtracting from 1601631 its sum of digits (18), we obtain a cube (1601613 = 117³).

Adding to 1601631 its reverse (1361061), we get a palindrome (2962692).

The spelling of 1601631 in words is "one million, six hundred one thousand, six hundred thirty-one".