20291289878 has 32 divisors (see below), whose sum is σ = 32058519552. Its totient is φ = 9618991200.

The previous prime is 20291289877. The next prime is 20291289901. The reversal of 20291289878 is 87898219202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20291289871) 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, 2437343 + ... + 2445653.

It is an arithmetic number, because the mean of its divisors is an integer number (1001828736).

Almost surely, 2^20291289878 is an apocalyptic number.

20291289878 is a deficient number, since it is larger than the sum of its proper divisors (11767229674).

20291289878 is a wasteful number, since it uses less digits than its factorization.

20291289878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9140.

The product of its (nonzero) digits is 2322432, while the sum is 56.

The spelling of 20291289878 in words is "twenty billion, two hundred ninety-one million, two hundred eighty-nine thousand, eight hundred seventy-eight".