20178140 has 24 divisors (see below), whose sum is σ = 42463680. Its totient is φ = 8054208.

The previous prime is 20178139. The next prime is 20178143. The reversal of 20178140 is 4187102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20178143) 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, 13469 + ... + 14891.

It is an arithmetic number, because the mean of its divisors is an integer number (1769320).

Almost surely, 2^20178140 is an apocalyptic number.

20178140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20178140 is an abundant number, since it is smaller than the sum of its proper divisors (22285540).

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

20178140 is a wasteful number, since it uses less digits than its factorization.

20178140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2141 (or 2139 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 20178140 is about 4492.0084594756. The cubic root of 20178140 is about 272.2452912716.

The spelling of 20178140 in words is "twenty million, one hundred seventy-eight thousand, one hundred forty".