131191901 has 2 divisors, whose sum is σ = 131191902. Its totient is φ = 131191900.

The previous prime is 131191897. The next prime is 131191937. The reversal of 131191901 is 109191131.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 131102500 + 89401 = 11450^2 + 299^2 .

It is a cyclic number.

It is not a de Polignac number, because 131191901 - 2² = 131191897 is a prime.

It is a super-2 number, since 2×131191901² = 34422629775987602, which contains 22 as substring.

It is equal to p_7442009 and since 131191901 and 7442009 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131191301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65595950 + 65595951.

It is an arithmetic number, because the mean of its divisors is an integer number (65595951).

Almost surely, 2^131191901 is an apocalyptic number.

It is an amenable number.

131191901 is a deficient number, since it is larger than the sum of its proper divisors (1).

131191901 is an equidigital number, since it uses as much as digits as its factorization.

131191901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 243, while the sum is 26.

The square root of 131191901 is about 11453.9033084796. The cubic root of 131191901 is about 508.1231811664.

The spelling of 131191901 in words is "one hundred thirty-one million, one hundred ninety-one thousand, nine hundred one".