131330021621 has 4 divisors (see below), whose sum is σ = 132166518732. Its totient is φ = 130493524512.

The previous prime is 131330021587. The next prime is 131330021671. The reversal of 131330021621 is 126120033131.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 53494601521 + 77835420100 = 231289^2 + 278990^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131330021621 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 (131330021671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 418248320 + ... + 418248633.

It is an arithmetic number, because the mean of its divisors is an integer number (33041629683).

Almost surely, 2^131330021621 is an apocalyptic number.

It is an amenable number.

131330021621 is a deficient number, since it is larger than the sum of its proper divisors (836497111).

131330021621 is an equidigital number, since it uses as much as digits as its factorization.

131330021621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 836497110.

The product of its (nonzero) digits is 648, while the sum is 23.

Adding to 131330021621 its reverse (126120033131), we get a palindrome (257450054752).

The spelling of 131330021621 in words is "one hundred thirty-one billion, three hundred thirty million, twenty-one thousand, six hundred twenty-one".