21950380998 has 128 divisors (see below), whose sum is σ = 60777507840. Its totient is φ = 5789006496.

The previous prime is 21950380987. The next prime is 21950381041. The reversal of 21950380998 is 89908305912.

It is a Harshad number since it is a multiple of its sum of digits (54).

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 63 ways as a sum of consecutive naturals, for example, 370461 + ... + 425607.

It is an arithmetic number, because the mean of its divisors is an integer number (474824280).

Almost surely, 2^21950380998 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21950380998, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30388753920).

21950380998 is an abundant number, since it is smaller than the sum of its proper divisors (38827126842).

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

21950380998 is an equidigital number, since it uses as much as digits as its factorization.

21950380998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55190 (or 55172 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 54.

The spelling of 21950380998 in words is "twenty-one billion, nine hundred fifty million, three hundred eighty thousand, nine hundred ninety-eight".