20668810 has 32 divisors (see below), whose sum is σ = 38662272. Its totient is φ = 7949760.

The previous prime is 20668799. The next prime is 20668811. The reversal of 20668810 is 1886602.

It is a super-2 number, since 2×20668810² = 854399413632200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20668811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30192 + ... + 30868.

It is an arithmetic number, because the mean of its divisors is an integer number (1208196).

Almost surely, 2^20668810 is an apocalyptic number.

20668810 is a deficient number, since it is larger than the sum of its proper divisors (17993462).

20668810 is a wasteful number, since it uses less digits than its factorization.

20668810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 798.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 20668810 is about 4546.2962947877. The cubic root of 20668810 is about 274.4343635335.

The spelling of 20668810 in words is "twenty million, six hundred sixty-eight thousand, eight hundred ten".