20217942 has 12 divisors (see below), whose sum is σ = 43805580. Its totient is φ = 6739308.

The previous prime is 20217941. The next prime is 20217949. The reversal of 20217942 is 24971202.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20217941) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 561592 + ... + 561627.

It is an arithmetic number, because the mean of its divisors is an integer number (3650465).

Almost surely, 2^20217942 is an apocalyptic number.

20217942 is an abundant number, since it is smaller than the sum of its proper divisors (23587638).

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

20217942 is a wasteful number, since it uses less digits than its factorization.

20217942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1123227 (or 1123224 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 20217942 is about 4496.4365891225. The cubic root of 20217942 is about 272.4241777656.

The spelling of 20217942 in words is "twenty million, two hundred seventeen thousand, nine hundred forty-two".