20491140 has 48 divisors (see below), whose sum is σ = 57572928. Its totient is φ = 5445504.

The previous prime is 20491127. The next prime is 20491147. The reversal of 20491140 is 4119402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20491147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31054 + ... + 31706.

It is an arithmetic number, because the mean of its divisors is an integer number (1199436).

Almost surely, 2^20491140 is an apocalyptic number.

20491140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20491140 is an abundant number, since it is smaller than the sum of its proper divisors (37081788).

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

20491140 is a wasteful number, since it uses less digits than its factorization.

20491140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1188 (or 1186 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 20491140 is about 4526.7140400074. The cubic root of 20491140 is about 273.6457495912.

The spelling of 20491140 in words is "twenty million, four hundred ninety-one thousand, one hundred forty".