20616040 has 16 divisors (see below), whose sum is σ = 46386180. Its totient is φ = 8246400.

The previous prime is 20616031. The next prime is 20616041. The reversal of 20616040 is 4061602.

It can be written as a sum of positive squares in 2 ways, for example, as 19838116 + 777924 = 4454^2 + 882^2 .

It is a super-2 number, since 2×20616040² = 850042210563200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20615999 and 20616017.

It is not an unprimeable number, because it can be changed into a prime (20616041) 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, 257661 + ... + 257740.

Almost surely, 2^20616040 is an apocalyptic number.

20616040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20616040 is an abundant number, since it is smaller than the sum of its proper divisors (25770140).

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

20616040 is a wasteful number, since it uses less digits than its factorization.

20616040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515412 (or 515408 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 20616040 is about 4540.4889604535. The cubic root of 20616040 is about 274.2006096541.

Adding to 20616040 its reverse (4061602), we get a palindrome (24677642).

The spelling of 20616040 in words is "twenty million, six hundred sixteen thousand, forty".