21011764384967 has 4 divisors (see below), whose sum is σ = 21011789229576. Its totient is φ = 21011739540360.

The previous prime is 21011764384939. The next prime is 21011764384973. The reversal of 21011764384967 is 76948346711012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21011764384967 - 2¹⁶ = 21011764319431 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 (21011764084967) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11107313 + ... + 12860634.

It is an arithmetic number, because the mean of its divisors is an integer number (5252947307394).

Almost surely, 2^{21011764384967} is an apocalyptic number.

21011764384967 is a deficient number, since it is larger than the sum of its proper divisors (24844609).

21011764384967 is an equidigital number, since it uses as much as digits as its factorization.

21011764384967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24844608.

The product of its (nonzero) digits is 12192768, while the sum is 59.

The spelling of 21011764384967 in words is "twenty-one trillion, eleven billion, seven hundred sixty-four million, three hundred eighty-four thousand, nine hundred sixty-seven".