21619680390 has 384 divisors, whose sum is σ = 71866828800. Its totient is φ = 4379443200.

The previous prime is 21619680389. The next prime is 21619680403. The reversal of 21619680390 is 9308691612.

It is a happy number.

21619680390 is a `hidden beast` number, since 21 + 619 + 6 + 8 + 0 + 3 + 9 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 84123142 + ... + 84123398.

It is an arithmetic number, because the mean of its divisors is an integer number (187153200).

Almost surely, 2^21619680390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21619680390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35933414400).

21619680390 is an abundant number, since it is smaller than the sum of its proper divisors (50247148410).

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

21619680390 is a wasteful number, since it uses less digits than its factorization.

21619680390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548 (or 545 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The spelling of 21619680390 in words is "twenty-one billion, six hundred nineteen million, six hundred eighty thousand, three hundred ninety".