20580640 has 24 divisors (see below), whose sum is σ = 48622140. Its totient is φ = 8232192.

The previous prime is 20580631. The next prime is 20580649. The reversal of 20580640 is 4608502.

It is an interprime number because it is at equal distance from previous prime (20580631) and next prime (20580649).

It can be written as a sum of positive squares in 2 ways, for example, as 20539024 + 41616 = 4532^2 + 204^2 .

It is not an unprimeable number, because it can be changed into a prime (20580649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64155 + ... + 64474.

Almost surely, 2^20580640 is an apocalyptic number.

20580640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20580640 is an abundant number, since it is smaller than the sum of its proper divisors (28041500).

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

20580640 is a wasteful number, since it uses less digits than its factorization.

20580640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128644 (or 128636 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 20580640 is about 4536.5890270114. The cubic root of 20580640 is about 274.0435755727.

The spelling of 20580640 in words is "twenty million, five hundred eighty thousand, six hundred forty".