20542191870 has 32 divisors (see below), whose sum is σ = 50503733280. Its totient is φ = 5344309760.

The previous prime is 20542191853. The next prime is 20542191877. The reversal of 20542191870 is 7819124502.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20542191877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8349255 + ... + 8351714.

It is an arithmetic number, because the mean of its divisors is an integer number (1578241665).

Almost surely, 2^20542191870 is an apocalyptic number.

20542191870 is an abundant number, since it is smaller than the sum of its proper divisors (29961541410).

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

20542191870 is a wasteful number, since it uses less digits than its factorization.

20542191870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16701020.

The product of its (nonzero) digits is 40320, while the sum is 39.

The spelling of 20542191870 in words is "twenty billion, five hundred forty-two million, one hundred ninety-one thousand, eight hundred seventy".