21026187698 has 16 divisors (see below), whose sum is σ = 31615811136. Its totient is φ = 10487603280.

The previous prime is 21026187653. The next prime is 21026187713. The reversal of 21026187698 is 89678162012.

It is a super-2 number, since 2×21026187698² (a number of 21 digits) contains 22 as substring.

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, 4547828 + ... + 4552448.

It is an arithmetic number, because the mean of its divisors is an integer number (1975988196).

Almost surely, 2^21026187698 is an apocalyptic number.

21026187698 is a deficient number, since it is larger than the sum of its proper divisors (10589623438).

21026187698 is a wasteful number, since it uses less digits than its factorization.

21026187698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9649.

The product of its (nonzero) digits is 580608, while the sum is 50.

The spelling of 21026187698 in words is "twenty-one billion, twenty-six million, one hundred eighty-seven thousand, six hundred ninety-eight".