21450545637 has 8 divisors (see below), whose sum is σ = 29844237504. Its totient is φ = 13678608768.

The previous prime is 21450545609. The next prime is 21450545639. The reversal of 21450545637 is 73654505412.

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

It is not a de Polignac number, because 21450545637 - 2⁸ = 21450545381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21450545639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155438668 + ... + 155438805.

It is an arithmetic number, because the mean of its divisors is an integer number (3730529688).

Almost surely, 2^21450545637 is an apocalyptic number.

It is an amenable number.

21450545637 is a deficient number, since it is larger than the sum of its proper divisors (8393691867).

21450545637 is a wasteful number, since it uses less digits than its factorization.

21450545637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310877499.

The product of its (nonzero) digits is 504000, while the sum is 42.

The spelling of 21450545637 in words is "twenty-one billion, four hundred fifty million, five hundred forty-five thousand, six hundred thirty-seven".