20261808 has 60 divisors (see below), whose sum is σ = 64808848. Its totient is φ = 5788800.

The previous prime is 20261803. The next prime is 20261861. The reversal of 20261808 is 80816202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20261803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9043 + ... + 11058.

Almost surely, 2^20261808 is an apocalyptic number.

20261808 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20261808 is an abundant number, since it is smaller than the sum of its proper divisors (44547040).

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

20261808 is a wasteful number, since it uses less digits than its factorization.

20261808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20122 (or 20113 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 20261808 is about 4501.3118087953. The cubic root of 20261808 is about 272.6210577910.

The spelling of 20261808 in words is "twenty million, two hundred sixty-one thousand, eight hundred eight".