21699261858 has 32 divisors (see below), whose sum is σ = 43974086400. Its totient is φ = 7137720576.

The previous prime is 21699261853. The next prime is 21699261889. The reversal of 21699261858 is 85816299612.

It is a happy number.

It is a super-2 number, since 2×21699261858² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21699261798 and 21699261807.

It is not an unprimeable number, because it can be changed into a prime (21699261853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85383 + ... + 225141.

It is an arithmetic number, because the mean of its divisors is an integer number (1374190200).

Almost surely, 2^21699261858 is an apocalyptic number.

21699261858 is an abundant number, since it is smaller than the sum of its proper divisors (22274824542).

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

21699261858 is a wasteful number, since it uses less digits than its factorization.

21699261858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140106.

The product of its digits is 3732480, while the sum is 57.

The spelling of 21699261858 in words is "twenty-one billion, six hundred ninety-nine million, two hundred sixty-one thousand, eight hundred fifty-eight".