20715040 has 24 divisors (see below), whose sum is σ = 48939660. Its totient is φ = 8285952.

The previous prime is 20715007. The next prime is 20715041. The reversal of 20715040 is 4051702.

It can be written as a sum of positive squares in 2 ways, for example, as 18766224 + 1948816 = 4332^2 + 1396^2 .

It is a super-2 number, since 2×20715040² = 858225764403200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20714999 and 20715017.

It is not an unprimeable number, because it can be changed into a prime (20715041) 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, 64575 + ... + 64894.

Almost surely, 2^20715040 is an apocalyptic number.

20715040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20715040 is an abundant number, since it is smaller than the sum of its proper divisors (28224620).

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

20715040 is a wasteful number, since it uses less digits than its factorization.

20715040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129484 (or 129476 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 20715040 is about 4551.3778133660. The cubic root of 20715040 is about 274.6388206079.

Adding to 20715040 its reverse (4051702), we get a palindrome (24766742).

The spelling of 20715040 in words is "twenty million, seven hundred fifteen thousand, forty".