645406867137 has 8 divisors (see below), whose sum is σ = 875127955680. Its totient is φ = 422978511680.

The previous prime is 645406867121. The next prime is 645406867159. The reversal of 645406867137 is 731768604546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645406867137 - 2⁴ = 645406867121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645406867337) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1823183064 + ... + 1823183417.

It is an arithmetic number, because the mean of its divisors is an integer number (109390994460).

Almost surely, 2^645406867137 is an apocalyptic number.

It is an amenable number.

645406867137 is a deficient number, since it is larger than the sum of its proper divisors (229721088543).

645406867137 is a wasteful number, since it uses less digits than its factorization.

645406867137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3646366543.

The product of its (nonzero) digits is 20321280, while the sum is 57.

The spelling of 645406867137 in words is "six hundred forty-five billion, four hundred six million, eight hundred sixty-seven thousand, one hundred thirty-seven".