20187985401 has 32 divisors (see below), whose sum is σ = 32068339200. Its totient is φ = 12506607360.

The previous prime is 20187985331. The next prime is 20187985409. The reversal of 20187985401 is 10458978102.

20187985401 is a `hidden beast` number, since 2 + 0 + 18 + 7 + 98 + 540 + 1 = 666.

It is not a de Polignac number, because 20187985401 - 2¹⁷ = 20187854329 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20187985409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 242110 + ... + 314631.

It is an arithmetic number, because the mean of its divisors is an integer number (1002135600).

Almost surely, 2^20187985401 is an apocalyptic number.

It is an amenable number.

20187985401 is a deficient number, since it is larger than the sum of its proper divisors (11880353799).

20187985401 is a wasteful number, since it uses less digits than its factorization.

20187985401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556846 (or 556840 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 20187985401 in words is "twenty billion, one hundred eighty-seven million, nine hundred eighty-five thousand, four hundred one".