20521370859 has 16 divisors (see below), whose sum is σ = 29851912704. Its totient is φ = 12436092000.

The previous prime is 20521370843. The next prime is 20521370861. The reversal of 20521370859 is 95807312502.

It is a happy number.

It is not a de Polignac number, because 20521370859 - 2⁴ = 20521370843 is a prime.

It is a super-2 number, since 2×20521370859² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20521370859.

It is not an unprimeable number, because it can be changed into a prime (20521370809) 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, 502509 + ... + 541809.

It is an arithmetic number, because the mean of its divisors is an integer number (1865744544).

Almost surely, 2^20521370859 is an apocalyptic number.

20521370859 is a deficient number, since it is larger than the sum of its proper divisors (9330541845).

20521370859 is a wasteful number, since it uses less digits than its factorization.

20521370859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55138.

The product of its (nonzero) digits is 151200, while the sum is 42.

The spelling of 20521370859 in words is "twenty billion, five hundred twenty-one million, three hundred seventy thousand, eight hundred fifty-nine".