21628351207 has 4 divisors (see below), whose sum is σ = 21629225880. Its totient is φ = 21627476536.

The previous prime is 21628351181. The next prime is 21628351229. The reversal of 21628351207 is 70215382612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21628351207 - 2¹¹ = 21628349159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21628351237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 399133 + ... + 450070.

It is an arithmetic number, because the mean of its divisors is an integer number (5407306470).

Almost surely, 2^21628351207 is an apocalyptic number.

21628351207 is a deficient number, since it is larger than the sum of its proper divisors (874673).

21628351207 is an equidigital number, since it uses as much as digits as its factorization.

21628351207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 874672.

The product of its (nonzero) digits is 40320, while the sum is 37.

The spelling of 21628351207 in words is "twenty-one billion, six hundred twenty-eight million, three hundred fifty-one thousand, two hundred seven".