21450420366 has 8 divisors (see below), whose sum is σ = 42900840744. Its totient is φ = 7150140120.

The previous prime is 21450420359. The next prime is 21450420371. The reversal of 21450420366 is 66302405412.

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

21450420366 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1787535025 + ... + 1787535036.

It is an arithmetic number, because the mean of its divisors is an integer number (5362605093).

Almost surely, 2^21450420366 is an apocalyptic number.

21450420366 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21450420366 is a wasteful number, since it uses less digits than its factorization.

21450420366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3575070066.

The product of its (nonzero) digits is 34560, while the sum is 33.

Adding to 21450420366 its reverse (66302405412), we get a palindrome (87752825778).

The spelling of 21450420366 in words is "twenty-one billion, four hundred fifty million, four hundred twenty thousand, three hundred sixty-six".