21450267449 has 8 divisors (see below), whose sum is σ = 23359843080. Its totient is φ = 19577771136.

The previous prime is 21450267427. The next prime is 21450267481. The reversal of 21450267449 is 94476205412.

It can be written as a sum of positive squares in 4 ways, for example, as 1837665424 + 19612602025 = 42868^2 + 140045^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21450267449 is a prime.

It is a super-2 number, since 2×21450267449² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21450267499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9268622 + ... + 9270935.

It is an arithmetic number, because the mean of its divisors is an integer number (2919980385).

Almost surely, 2^21450267449 is an apocalyptic number.

It is an amenable number.

21450267449 is a deficient number, since it is larger than the sum of its proper divisors (1909575631).

21450267449 is a wasteful number, since it uses less digits than its factorization.

21450267449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18539659.

The product of its (nonzero) digits is 483840, while the sum is 44.

The spelling of 21450267449 in words is "twenty-one billion, four hundred fifty million, two hundred sixty-seven thousand, four hundred forty-nine".