21989943519 has 16 divisors (see below), whose sum is σ = 29815420512. Its totient is φ = 14413483008.

The previous prime is 21989943517. The next prime is 21989943601. The reversal of 21989943519 is 91534998912.

It is not a de Polignac number, because 21989943519 - 2¹ = 21989943517 is a prime.

It is a super-2 number, since 2×21989943519² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21989943517) 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, 88954 + ... + 227799.

It is an arithmetic number, because the mean of its divisors is an integer number (1863463782).

Almost surely, 2^21989943519 is an apocalyptic number.

21989943519 is a deficient number, since it is larger than the sum of its proper divisors (7825476993).

21989943519 is a wasteful number, since it uses less digits than its factorization.

21989943519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317146.

The product of its digits is 6298560, while the sum is 60.

The spelling of 21989943519 in words is "twenty-one billion, nine hundred eighty-nine million, nine hundred forty-three thousand, five hundred nineteen".