645416266661157 has 4 divisors (see below), whose sum is σ = 860555022214880. Its totient is φ = 430277511107436.

The previous prime is 645416266661063. The next prime is 645416266661197. The reversal of 645416266661157 is 751166662614546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 645416266661157 - 2¹⁵ = 645416266628389 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 (645416266661197) 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, 107569377776857 + ... + 107569377776862.

It is an arithmetic number, because the mean of its divisors is an integer number (215138755553720).

Almost surely, 2^{645416266661157} is an apocalyptic number.

It is an amenable number.

645416266661157 is a deficient number, since it is larger than the sum of its proper divisors (215138755553723).

645416266661157 is a wasteful number, since it uses less digits than its factorization.

645416266661157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215138755553722.

The product of its digits is 261273600, while the sum is 66.

The spelling of 645416266661157 in words is "six hundred forty-five trillion, four hundred sixteen billion, two hundred sixty-six million, six hundred sixty-one thousand, one hundred fifty-seven".