21890967269 has 4 divisors (see below), whose sum is σ = 23178671244. Its totient is φ = 20603263296.

The previous prime is 21890967257. The next prime is 21890967299. The reversal of 21890967269 is 96276909812.

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 9000316900 + 12890650369 = 94870^2 + 113537^2 .

It is a cyclic number.

It is not a de Polignac number, because 21890967269 - 2¹⁶ = 21890901733 is a prime.

It is a super-2 number, since 2×21890967269² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21890967299) 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, 643851962 + ... + 643851995.

It is an arithmetic number, because the mean of its divisors is an integer number (5794667811).

Almost surely, 2^21890967269 is an apocalyptic number.

It is an amenable number.

21890967269 is a deficient number, since it is larger than the sum of its proper divisors (1287703975).

21890967269 is a wasteful number, since it uses less digits than its factorization.

21890967269 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1287703974.

The product of its (nonzero) digits is 5878656, while the sum is 59.

The spelling of 21890967269 in words is "twenty-one billion, eight hundred ninety million, nine hundred sixty-seven thousand, two hundred sixty-nine".