131649138 has 96 divisors (see below), whose sum is σ = 318427200. Its totient is φ = 40637376.

The previous prime is 131649137. The next prime is 131649143. The reversal of 131649138 is 831946131.

131649138 is a `hidden beast` number, since 1 + 3 + 1 + 649 + 1 + 3 + 8 = 666.

It is a super-2 number, since 2×131649138² = 34662991072286088, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (131649137) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 489268 + ... + 489536.

It is an arithmetic number, because the mean of its divisors is an integer number (3316950).

Almost surely, 2^131649138 is an apocalyptic number.

131649138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 131649138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159213600).

131649138 is an abundant number, since it is smaller than the sum of its proper divisors (186778062).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

131649138 is a wasteful number, since it uses less digits than its factorization.

131649138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358 (or 346 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 131649138 is about 11473.8458243084. The cubic root of 131649138 is about 508.7128093519.

The spelling of 131649138 in words is "one hundred thirty-one million, six hundred forty-nine thousand, one hundred thirty-eight".