21989643013 has 16 divisors (see below), whose sum is σ = 24506814976. Its totient is φ = 19593731520.

The previous prime is 21989643007. The next prime is 21989643019. The reversal of 21989643013 is 31034698912.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21989643007) and next prime (21989643019).

It is a cyclic number.

It is not a de Polignac number, because 21989643013 - 2¹⁷ = 21989511941 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21989643019) 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, 91270 + ... + 228712.

It is an arithmetic number, because the mean of its divisors is an integer number (1531675936).

Almost surely, 2^21989643013 is an apocalyptic number.

It is an amenable number.

21989643013 is a deficient number, since it is larger than the sum of its proper divisors (2517171963).

21989643013 is a wasteful number, since it uses less digits than its factorization.

21989643013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137884.

The product of its (nonzero) digits is 279936, while the sum is 46.

The spelling of 21989643013 in words is "twenty-one billion, nine hundred eighty-nine million, six hundred forty-three thousand, thirteen".