131897221 has 8 divisors (see below), whose sum is σ = 139244000. Its totient is φ = 124590960.

The previous prime is 131897201. The next prime is 131897257. The reversal of 131897221 is 122798131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 5-Lehmer number, since φ(131897221) divides (131897221-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 131897221 - 2⁷ = 131897093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131897201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3315 + ... + 16576.

It is an arithmetic number, because the mean of its divisors is an integer number (17405500).

Almost surely, 2^131897221 is an apocalyptic number.

131897221 is the 6631-st octagonal number.

It is an amenable number.

131897221 is a deficient number, since it is larger than the sum of its proper divisors (7346779).

131897221 is a wasteful number, since it uses less digits than its factorization.

131897221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20259.

The product of its digits is 6048, while the sum is 34.

The square root of 131897221 is about 11484.6515402079. The cubic root of 131897221 is about 509.0321526490.

The spelling of 131897221 in words is "one hundred thirty-one million, eight hundred ninety-seven thousand, two hundred twenty-one".