131621616 has 120 divisors (see below), whose sum is σ = 445801824. Its totient is φ = 35389440.

The previous prime is 131621597. The next prime is 131621627. The reversal of 131621616 is 616126131.

131621616 is a `hidden beast` number, since 1 + 31 + 621 + 6 + 1 + 6 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 131621616.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13296 + ... + 20976.

Almost surely, 2^131621616 is an apocalyptic number.

131621616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 131621616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222900912).

131621616 is an abundant number, since it is smaller than the sum of its proper divisors (314180208).

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

131621616 is a wasteful number, since it uses less digits than its factorization.

131621616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7719 (or 7710 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 131621616 is about 11472.6464253022. The cubic root of 131621616 is about 508.6773571139.

Adding to 131621616 its reverse (616126131), we get a palindrome (747747747).

The spelling of 131621616 in words is "one hundred thirty-one million, six hundred twenty-one thousand, six hundred sixteen".