131721504 has 48 divisors (see below), whose sum is σ = 347276160. Its totient is φ = 43715840.

The previous prime is 131721497. The next prime is 131721521. The reversal of 131721504 is 405127131.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-3 number, since 3×131721504³ (a number of 25 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20074 + ... + 25814.

It is an arithmetic number, because the mean of its divisors is an integer number (7234920).

Almost surely, 2^131721504 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 131721504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173638080).

131721504 is an abundant number, since it is smaller than the sum of its proper divisors (215554656).

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

131721504 is a wasteful number, since it uses less digits than its factorization.

131721504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5993 (or 5985 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 131721504 is about 11476.9989108652. The cubic root of 131721504 is about 508.8060034496.

Adding to 131721504 its reverse (405127131), we get a palindrome (536848635).

The spelling of 131721504 in words is "one hundred thirty-one million, seven hundred twenty-one thousand, five hundred four".