355661894981 has 2 divisors, whose sum is σ = 355661894982. Its totient is φ = 355661894980.

The previous prime is 355661894977. The next prime is 355661894993. The reversal of 355661894981 is 189498166553.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 303567940900 + 52093954081 = 550970^2 + 228241^2 .

It is a cyclic number.

It is not a de Polignac number, because 355661894981 - 2² = 355661894977 is a prime.

It is a super-2 number, since 2×355661894981² (a number of 24 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (355661894921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 177830947490 + 177830947491.

It is an arithmetic number, because the mean of its divisors is an integer number (177830947491).

Almost surely, 2^355661894981 is an apocalyptic number.

It is an amenable number.

355661894981 is a deficient number, since it is larger than the sum of its proper divisors (1).

355661894981 is an equidigital number, since it uses as much as digits as its factorization.

355661894981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 55987200, while the sum is 65.

The spelling of 355661894981 in words is "three hundred fifty-five billion, six hundred sixty-one million, eight hundred ninety-four thousand, nine hundred eighty-one".