645877483940 has 36 divisors (see below), whose sum is σ = 1468702475604. Its totient is φ = 238477838976.

The previous prime is 645877483897. The next prime is 645877483943. The reversal of 645877483940 is 49384778546.

It can be written as a sum of positive squares in 6 ways, for example, as 68681733184 + 577195750756 = 262072^2 + 759734^2 .

It is a Harshad number since it is a multiple of its sum of digits (65).

It is not an unprimeable number, because it can be changed into a prime (645877483943) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 95540627 + ... + 95547386.

It is an arithmetic number, because the mean of its divisors is an integer number (40797290989).

Almost surely, 2^645877483940 is an apocalyptic number.

It is an amenable number.

645877483940 is an abundant number, since it is smaller than the sum of its proper divisors (822824991664).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645877483940 is a wasteful number, since it uses less digits than its factorization.

645877483940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191088048 (or 191088033 counting only the distinct ones).

The product of its (nonzero) digits is 162570240, while the sum is 65.

The spelling of 645877483940 in words is "six hundred forty-five billion, eight hundred seventy-seven million, four hundred eighty-three thousand, nine hundred forty".