131220101 has 2 divisors, whose sum is σ = 131220102. Its totient is φ = 131220100.

The previous prime is 131220079. The next prime is 131220143. The reversal of 131220101 is 101022131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73444900 + 57775201 = 8570^2 + 7601^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131220101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131220151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65610050 + 65610051.

It is an arithmetic number, because the mean of its divisors is an integer number (65610051).

Almost surely, 2^131220101 is an apocalyptic number.

It is an amenable number.

131220101 is a deficient number, since it is larger than the sum of its proper divisors (1).

131220101 is an equidigital number, since it uses as much as digits as its factorization.

131220101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 131220101 is about 11455.1342637265. The cubic root of 131220101 is about 508.1595859725.

Adding to 131220101 its reverse (101022131), we get a palindrome (232242232).

The spelling of 131220101 in words is "one hundred thirty-one million, two hundred twenty thousand, one hundred one".