20402686 has 16 divisors (see below), whose sum is σ = 32495904. Its totient is φ = 9574144.

The previous prime is 20402663. The next prime is 20402687. The reversal of 20402686 is 68620402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20402687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16506 + ... + 17698.

It is an arithmetic number, because the mean of its divisors is an integer number (2030994).

Almost surely, 2^20402686 is an apocalyptic number.

20402686 is a deficient number, since it is larger than the sum of its proper divisors (12093218).

20402686 is a wasteful number, since it uses less digits than its factorization.

20402686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1715.

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 20402686 is about 4516.9332516653. The cubic root of 20402686 is about 273.2514332587.

The spelling of 20402686 in words is "twenty million, four hundred two thousand, six hundred eighty-six".