20428820839 has 24 divisors (see below), whose sum is σ = 24014492160. Its totient is φ = 17326685376.

The previous prime is 20428820833. The next prime is 20428820879. The reversal of 20428820839 is 93802882402.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-20428820839 is a prime.

It is a super-4 number, since 4×20428820839⁴ (a number of 42 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20428820833) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2466397 + ... + 2474665.

It is an arithmetic number, because the mean of its divisors is an integer number (1000603840).

Almost surely, 2^20428820839 is an apocalyptic number.

20428820839 is a deficient number, since it is larger than the sum of its proper divisors (3585671321).

20428820839 is a wasteful number, since it uses less digits than its factorization.

20428820839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8807 (or 8800 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 46.

The spelling of 20428820839 in words is "twenty billion, four hundred twenty-eight million, eight hundred twenty thousand, eight hundred thirty-nine".