640246701870 has 48 divisors (see below), whose sum is σ = 1726294817520. Its totient is φ = 170732453184.

The previous prime is 640246701847. The next prime is 640246701907. The reversal of 640246701870 is 78107642046.

640246701870 is a `hidden beast` number, since 6 + 4 + 0 + 2 + 467 + 0 + 187 + 0 = 666.

It is a super-2 number, since 2×640246701870² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 131735575 + ... + 131740434.

It is an arithmetic number, because the mean of its divisors is an integer number (35964475365).

Almost surely, 2^640246701870 is an apocalyptic number.

640246701870 is an abundant number, since it is smaller than the sum of its proper divisors (1086048115650).

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

640246701870 is a wasteful number, since it uses less digits than its factorization.

640246701870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263476031 (or 263476019 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The spelling of 640246701870 in words is "six hundred forty billion, two hundred forty-six million, seven hundred one thousand, eight hundred seventy".