165311643451 has 2 divisors, whose sum is σ = 165311643452. Its totient is φ = 165311643450.

The previous prime is 165311643449. The next prime is 165311643493. The reversal of 165311643451 is 154346113561.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 165311643451 - 2¹ = 165311643449 is a prime.

Together with 165311643449, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (165311643251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82655821725 + 82655821726.

It is an arithmetic number, because the mean of its divisors is an integer number (82655821726).

Almost surely, 2^165311643451 is an apocalyptic number.

165311643451 is a deficient number, since it is larger than the sum of its proper divisors (1).

165311643451 is an equidigital number, since it uses as much as digits as its factorization.

165311643451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 40.

The spelling of 165311643451 in words is "one hundred sixty-five billion, three hundred eleven million, six hundred forty-three thousand, four hundred fifty-one".