20421854 has 32 divisors (see below), whose sum is σ = 33094656. Its totient is φ = 9434880.

The previous prime is 20421803. The next prime is 20421859. The reversal of 20421854 is 45812402.

It is a happy number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421859) 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, 160739 + ... + 160865.

It is an arithmetic number, because the mean of its divisors is an integer number (1034208).

Almost surely, 2^20421854 is an apocalyptic number.

20421854 is a deficient number, since it is larger than the sum of its proper divisors (12672802).

20421854 is a wasteful number, since it uses less digits than its factorization.

20421854 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260.

The product of its (nonzero) digits is 2560, while the sum is 26.

The square root of 20421854 is about 4519.0545471370. The cubic root of 20421854 is about 273.3369782712.

The spelling of 20421854 in words is "twenty million, four hundred twenty-one thousand, eight hundred fifty-four".