20428984899 has 24 divisors (see below), whose sum is σ = 30315815712. Its totient is φ = 13246968960.

The previous prime is 20428984897. The next prime is 20428984913. The reversal of 20428984899 is 99848982402.

20428984899 is a `hidden beast` number, since 20 + 42 + 8 + 98 + 489 + 9 = 666.

It is a Cunningham number, because it is equal to 142930²-1.

It is not a de Polignac number, because 20428984899 - 2¹ = 20428984897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20428984897) 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, 1278439 + ... + 1294319.

It is an arithmetic number, because the mean of its divisors is an integer number (1263158988).

Almost surely, 2^20428984899 is an apocalyptic number.

20428984899 is a deficient number, since it is larger than the sum of its proper divisors (9886830813).

20428984899 is a wasteful number, since it uses less digits than its factorization.

20428984899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19787 (or 19784 counting only the distinct ones).

The product of its (nonzero) digits is 23887872, while the sum is 63.

The spelling of 20428984899 in words is "twenty billion, four hundred twenty-eight million, nine hundred eighty-four thousand, eight hundred ninety-nine".