645701422127 has 4 divisors (see below), whose sum is σ = 645703055016. Its totient is φ = 645699789240.

The previous prime is 645701422109. The next prime is 645701422129. The reversal of 645701422127 is 721224107546.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 645701422127 - 2¹⁰ = 645701421103 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 (645701422129) 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, 191477 + ... + 1152417.

It is an arithmetic number, because the mean of its divisors is an integer number (161425763754).

Almost surely, 2^645701422127 is an apocalyptic number.

645701422127 is a deficient number, since it is larger than the sum of its proper divisors (1632889).

645701422127 is an equidigital number, since it uses as much as digits as its factorization.

645701422127 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1632888.

The product of its (nonzero) digits is 188160, while the sum is 41.

The spelling of 645701422127 in words is "six hundred forty-five billion, seven hundred one million, four hundred twenty-two thousand, one hundred twenty-seven".