21250640345 has 32 divisors (see below), whose sum is σ = 29409194880. Its totient is φ = 14578583040.

The previous prime is 21250640317. The next prime is 21250640351. The reversal of 21250640345 is 54304605212.

It is not a de Polignac number, because 21250640345 - 2²⁴ = 21233863129 is a prime.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 199847 + ... + 287123.

It is an arithmetic number, because the mean of its divisors is an integer number (919037340).

Almost surely, 2^21250640345 is an apocalyptic number.

It is an amenable number.

21250640345 is a deficient number, since it is larger than the sum of its proper divisors (8158554535).

21250640345 is a wasteful number, since it uses less digits than its factorization.

21250640345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87545.

The product of its (nonzero) digits is 28800, while the sum is 32.

The spelling of 21250640345 in words is "twenty-one billion, two hundred fifty million, six hundred forty thousand, three hundred forty-five".