28210193820 has 36 divisors (see below), whose sum is σ = 85570921800. Its totient is φ = 7522718304.

The previous prime is 28210193761. The next prime is 28210193833. The reversal of 28210193820 is 2839101282.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 78361470 + ... + 78361829.

It is an arithmetic number, because the mean of its divisors is an integer number (2376970050).

Almost surely, 2^28210193820 is an apocalyptic number.

28210193820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28210193820 is an abundant number, since it is smaller than the sum of its proper divisors (57360727980).

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

28210193820 is a wasteful number, since it uses less digits than its factorization.

28210193820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156723314 (or 156723309 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The spelling of 28210193820 in words is "twenty-eight billion, two hundred ten million, one hundred ninety-three thousand, eight hundred twenty".