131521420 has 48 divisors (see below), whose sum is σ = 291997440. Its totient is φ = 49622976.

The previous prime is 131521393. The next prime is 131521433. The reversal of 131521420 is 24125131.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 106929 + ... + 108151.

It is an arithmetic number, because the mean of its divisors is an integer number (6083280).

Almost surely, 2^131521420 is an apocalyptic number.

131521420 is a gapful number since it is divisible by the number (10) 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 131521420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145998720).

131521420 is an abundant number, since it is smaller than the sum of its proper divisors (160476020).

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

131521420 is a wasteful number, since it uses less digits than its factorization.

131521420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1534 (or 1532 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 131521420 is about 11468.2788595325. The cubic root of 131521420 is about 508.5482486985.

Adding to 131521420 its reverse (24125131), we get a palindrome (155646551).

The spelling of 131521420 in words is "one hundred thirty-one million, five hundred twenty-one thousand, four hundred twenty".