20423820 has 24 divisors (see below), whose sum is σ = 57186864. Its totient is φ = 5446336.

The previous prime is 20423813. The next prime is 20423831. The reversal of 20423820 is 2832402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 170139 + ... + 170258.

It is an arithmetic number, because the mean of its divisors is an integer number (2382786).

Almost surely, 2^20423820 is an apocalyptic number.

20423820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20423820 is an abundant number, since it is smaller than the sum of its proper divisors (36763044).

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

20423820 is a wasteful number, since it uses less digits than its factorization.

20423820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340409 (or 340407 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 20423820 is about 4519.2720652778. The cubic root of 20423820 is about 273.3457493203.

The spelling of 20423820 in words is "twenty million, four hundred twenty-three thousand, eight hundred twenty".