20028478236 has 24 divisors (see below), whose sum is σ = 50327971344. Its totient is φ = 6162608640.

The previous prime is 20028478213. The next prime is 20028478259. The reversal of 20028478236 is 63287482002.

It is an interprime number because it is at equal distance from previous prime (20028478213) and next prime (20028478259).

It is a super-2 number, since 2×20028478236² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64193685 + ... + 64193996.

It is an arithmetic number, because the mean of its divisors is an integer number (2096998806).

Almost surely, 2^20028478236 is an apocalyptic number.

20028478236 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20028478236 is an abundant number, since it is smaller than the sum of its proper divisors (30299493108).

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

20028478236 is a wasteful number, since it uses less digits than its factorization.

20028478236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128387701 (or 128387699 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 42.

The spelling of 20028478236 in words is "twenty billion, twenty-eight million, four hundred seventy-eight thousand, two hundred thirty-six".