21034658969 has 4 divisors (see below), whose sum is σ = 21110596644. Its totient is φ = 20958721296.

The previous prime is 21034658951. The next prime is 21034658999. The reversal of 21034658969 is 96985643012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11699234569 + 9335424400 = 108163^2 + 96620^2 .

It is a cyclic number.

It is not a de Polignac number, because 21034658969 - 2⁸ = 21034658713 is a prime.

It is a super-2 number, since 2×21034658969² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21034658969.

It is not an unprimeable number, because it can be changed into a prime (21034658929) 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, 37968422 + ... + 37968975.

It is an arithmetic number, because the mean of its divisors is an integer number (5277649161).

Almost surely, 2^21034658969 is an apocalyptic number.

It is an amenable number.

21034658969 is a deficient number, since it is larger than the sum of its proper divisors (75937675).

21034658969 is an equidigital number, since it uses as much as digits as its factorization.

21034658969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75937674.

The product of its (nonzero) digits is 2799360, while the sum is 53.

The spelling of 21034658969 in words is "twenty-one billion, thirty-four million, six hundred fifty-eight thousand, nine hundred sixty-nine".