20825517858 has 32 divisors (see below), whose sum is σ = 42935883840. Its totient is φ = 6729094080.

The previous prime is 20825517833. The next prime is 20825517859. The reversal of 20825517858 is 85871552802.

It is a self number, because there is not a number n which added to its sum of digits gives 20825517858.

It is not an unprimeable number, because it can be changed into a prime (20825517859) 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, 114648 + ... + 234083.

It is an arithmetic number, because the mean of its divisors is an integer number (1341746370).

Almost surely, 2^20825517858 is an apocalyptic number.

20825517858 is an abundant number, since it is smaller than the sum of its proper divisors (22110365982).

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

20825517858 is a wasteful number, since it uses less digits than its factorization.

20825517858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349042.

The product of its (nonzero) digits is 1792000, while the sum is 51.

The spelling of 20825517858 in words is "twenty billion, eight hundred twenty-five million, five hundred seventeen thousand, eight hundred fifty-eight".