356440209121 has 2 divisors, whose sum is σ = 356440209122. Its totient is φ = 356440209120.

The previous prime is 356440209119. The next prime is 356440209157. The reversal of 356440209121 is 121902044653.

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., 241223411025 + 115216798096 = 491145^2 + 339436^2 .

It is a cyclic number.

It is not a de Polignac number, because 356440209121 - 2¹ = 356440209119 is a prime.

Together with 356440209119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (356440209221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 178220104560 + 178220104561.

It is an arithmetic number, because the mean of its divisors is an integer number (178220104561).

Almost surely, 2^356440209121 is an apocalyptic number.

It is an amenable number.

356440209121 is a deficient number, since it is larger than the sum of its proper divisors (1).

356440209121 is an equidigital number, since it uses as much as digits as its factorization.

356440209121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 37.

The spelling of 356440209121 in words is "three hundred fifty-six billion, four hundred forty million, two hundred nine thousand, one hundred twenty-one".