20428693520 has 40 divisors (see below), whose sum is σ = 47525481240. Its totient is φ = 8166528000.

The previous prime is 20428693517. The next prime is 20428693531. The reversal of 20428693520 is 2539682402.

It can be written as a sum of positive squares in 4 ways, for example, as 24285184 + 20404408336 = 4928^2 + 142844^2 .

It is a tau number, because it is divible by the number of its divisors (40).

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, 57020 + ... + 210020.

It is an arithmetic number, because the mean of its divisors is an integer number (1188137031).

Almost surely, 2^20428693520 is an apocalyptic number.

20428693520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20428693520 is an abundant number, since it is smaller than the sum of its proper divisors (27096787720).

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

20428693520 is a wasteful number, since it uses less digits than its factorization.

20428693520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154683 (or 154677 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 41.

The spelling of 20428693520 in words is "twenty billion, four hundred twenty-eight million, six hundred ninety-three thousand, five hundred twenty".