20021070640 has 40 divisors (see below), whose sum is σ = 48998939760. Its totient is φ = 7586931456.

The previous prime is 20021070631. The next prime is 20021070649. The reversal of 20021070640 is 4607012002.

It is an interprime number because it is at equal distance from previous prime (20021070631) and next prime (20021070649).

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (20021070649) 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, 6584359 + ... + 6587398.

It is an arithmetic number, because the mean of its divisors is an integer number (1224973494).

Almost surely, 2^20021070640 is an apocalyptic number.

20021070640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20021070640 is an abundant number, since it is smaller than the sum of its proper divisors (28977869120).

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

20021070640 is a wasteful number, since it uses less digits than its factorization.

20021070640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13171789 (or 13171783 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

Adding to 20021070640 its reverse (4607012002), we get a palindrome (24628082642).

The spelling of 20021070640 in words is "twenty billion, twenty-one million, seventy thousand, six hundred forty".