131821740 has 144 divisors (see below), whose sum is σ = 442024128. Its totient is φ = 31629312.

The previous prime is 131821693. The next prime is 131821783. The reversal of 131821740 is 47128131.

It is a super-2 number, since 2×131821740² = 34753942273255200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 69444 + ... + 71316.

It is an arithmetic number, because the mean of its divisors is an integer number (3069612).

Almost surely, 2^131821740 is an apocalyptic number.

131821740 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 131821740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221012064).

131821740 is an abundant number, since it is smaller than the sum of its proper divisors (310202388).

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

131821740 is a wasteful number, since it uses less digits than its factorization.

131821740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1928 (or 1923 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 131821740 is about 11481.3649014392. The cubic root of 131821740 is about 508.9350326155.

Adding to 131821740 its reverse (47128131), we get a palindrome (178949871).

The spelling of 131821740 in words is "one hundred thirty-one million, eight hundred twenty-one thousand, seven hundred forty".