20168940 has 48 divisors (see below), whose sum is σ = 61608960. Its totient is φ = 4889280.

The previous prime is 20168933. The next prime is 20168947. The reversal of 20168940 is 4986102.

It is an interprime number because it is at equal distance from previous prime (20168933) and next prime (20168947).

It is a super-3 number, since 3×20168940³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 20168898 and 20168907.

It is not an unprimeable number, because it can be changed into a prime (20168947) 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, 14620 + ... + 15939.

It is an arithmetic number, because the mean of its divisors is an integer number (1283520).

Almost surely, 2^20168940 is an apocalyptic number.

20168940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20168940 is an abundant number, since it is smaller than the sum of its proper divisors (41440020).

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

20168940 is a wasteful number, since it uses less digits than its factorization.

20168940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30582 (or 30580 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 20168940 is about 4490.9843019098. The cubic root of 20168940 is about 272.2039092375.

The spelling of 20168940 in words is "twenty million, one hundred sixty-eight thousand, nine hundred forty".