21487038198 has 16 divisors (see below), whose sum is σ = 43011361776. Its totient is φ = 7156131840.

The previous prime is 21487038161. The next prime is 21487038203. The reversal of 21487038198 is 89183078412.

It is a super-2 number, since 2×21487038198² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21487038198.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1546063 + ... + 1559898.

It is an arithmetic number, because the mean of its divisors is an integer number (2688210111).

Almost surely, 2^21487038198 is an apocalyptic number.

21487038198 is an abundant number, since it is smaller than the sum of its proper divisors (21524323578).

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

21487038198 is a wasteful number, since it uses less digits than its factorization.

21487038198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3107119.

The product of its (nonzero) digits is 774144, while the sum is 51.

The spelling of 21487038198 in words is "twenty-one billion, four hundred eighty-seven million, thirty-eight thousand, one hundred ninety-eight".