131821164 has 54 divisors (see below), whose sum is σ = 351553020. Its totient is φ = 41532912.

The previous prime is 131821147. The next prime is 131821189. The reversal of 131821164 is 461128131.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 300057 + ... + 300495.

Almost surely, 2^131821164 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 131821164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175776510).

131821164 is an abundant number, since it is smaller than the sum of its proper divisors (219731856).

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

131821164 is a wasteful number, since it uses less digits than its factorization.

131821164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 907 (or 463 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 131821164 is about 11481.3398172861. The cubic root of 131821164 is about 508.9342913442.

Adding to 131821164 its reverse (461128131), we get a palindrome (592949295).

The spelling of 131821164 in words is "one hundred thirty-one million, eight hundred twenty-one thousand, one hundred sixty-four".