20709900428 has 12 divisors (see below), whose sum is σ = 41419800912. Its totient is φ = 8875671600.

The previous prime is 20709900427. The next prime is 20709900439. The reversal of 20709900428 is 82400990702.

20709900428 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (20709900427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 369819623 + ... + 369819678.

It is an arithmetic number, because the mean of its divisors is an integer number (3451650076).

Almost surely, 2^20709900428 is an apocalyptic number.

20709900428 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20709900428 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20709900428 is a wasteful number, since it uses less digits than its factorization.

20709900428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739639312 (or 739639310 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 41.

The spelling of 20709900428 in words is "twenty billion, seven hundred nine million, nine hundred thousand, four hundred twenty-eight".