21542036469 has 4 divisors (see below), whose sum is σ = 28722715296. Its totient is φ = 14361357644.

The previous prime is 21542036459. The next prime is 21542036473. The reversal of 21542036469 is 96463024512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21542036469 - 2¹¹ = 21542034421 is a prime.

It is a super-2 number, since 2×21542036469² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21542036469.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21542036459) 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, 3590339409 + ... + 3590339414.

It is an arithmetic number, because the mean of its divisors is an integer number (7180678824).

Almost surely, 2^21542036469 is an apocalyptic number.

It is an amenable number.

21542036469 is a deficient number, since it is larger than the sum of its proper divisors (7180678827).

21542036469 is an equidigital number, since it uses as much as digits as its factorization.

21542036469 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7180678826.

The product of its (nonzero) digits is 311040, while the sum is 42.

The spelling of 21542036469 in words is "twenty-one billion, five hundred forty-two million, thirty-six thousand, four hundred sixty-nine".