131221810655 has 8 divisors (see below), whose sum is σ = 169578955392. Its totient is φ = 96902260128.

The previous prime is 131221810649. The next prime is 131221810661. The reversal of 131221810655 is 556018122131.

It is an interprime number because it is at equal distance from previous prime (131221810649) and next prime (131221810661).

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

It is a cyclic number.

It is not a de Polignac number, because 131221810655 - 2⁶ = 131221810591 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1009398479 + ... + 1009398608.

It is an arithmetic number, because the mean of its divisors is an integer number (21197369424).

Almost surely, 2^131221810655 is an apocalyptic number.

131221810655 is a deficient number, since it is larger than the sum of its proper divisors (38357144737).

131221810655 is a wasteful number, since it uses less digits than its factorization.

131221810655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2018797105.

The product of its (nonzero) digits is 14400, while the sum is 35.

Adding to 131221810655 its reverse (556018122131), we get a palindrome (687239932786).

The spelling of 131221810655 in words is "one hundred thirty-one billion, two hundred twenty-one million, eight hundred ten thousand, six hundred fifty-five".