20321675640 has 96 divisors (see below), whose sum is σ = 75480518880. Its totient is φ = 4644953856.

The previous prime is 20321675629. The next prime is 20321675657. The reversal of 20321675640 is 4657612302.

20321675640 is a `hidden beast` number, since 2 + 0 + 3 + 2 + 1 + 6 + 7 + 5 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 20321675595 and 20321675604.

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, 4029559 + ... + 4034598.

It is an arithmetic number, because the mean of its divisors is an integer number (786255405).

Almost surely, 2^20321675640 is an apocalyptic number.

20321675640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20321675640 is an abundant number, since it is smaller than the sum of its proper divisors (55158843240).

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

20321675640 is a wasteful number, since it uses less digits than its factorization.

20321675640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8064181 (or 8064174 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The spelling of 20321675640 in words is "twenty billion, three hundred twenty-one million, six hundred seventy-five thousand, six hundred forty".