21986298642 has 64 divisors (see below), whose sum is σ = 54904034304. Its totient is φ = 5702283840.

The previous prime is 21986298623. The next prime is 21986298731. The reversal of 21986298642 is 24689268912.

It is a happy number.

It is a super-2 number, since 2×21986298642² (a number of 21 digits) contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 280708 + ... + 350384.

It is an arithmetic number, because the mean of its divisors is an integer number (857875536).

Almost surely, 2^21986298642 is an apocalyptic number.

21986298642 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21986298642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27452017152).

21986298642 is an abundant number, since it is smaller than the sum of its proper divisors (32917735662).

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

21986298642 is a wasteful number, since it uses less digits than its factorization.

21986298642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70383.

The product of its digits is 5971968, while the sum is 57.

The spelling of 21986298642 in words is "twenty-one billion, nine hundred eighty-six million, two hundred ninety-eight thousand, six hundred forty-two".