21891435093 has 12 divisors (see below), whose sum is σ = 34495594848. Its totient is φ = 13267536360.

The previous prime is 21891435091. The next prime is 21891435101. The reversal of 21891435093 is 39053419812.

It is a happy number.

21891435093 is a `hidden beast` number, since 2 + 18 + 91 + 43 + 509 + 3 = 666.

It is not a de Polignac number, because 21891435093 - 2¹ = 21891435091 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21891435091) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 110562705 + ... + 110562902.

It is an arithmetic number, because the mean of its divisors is an integer number (2874632904).

Almost surely, 2^21891435093 is an apocalyptic number.

It is an amenable number.

21891435093 is a deficient number, since it is larger than the sum of its proper divisors (12604159755).

21891435093 is a wasteful number, since it uses less digits than its factorization.

21891435093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221125624 (or 221125621 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The spelling of 21891435093 in words is "twenty-one billion, eight hundred ninety-one million, four hundred thirty-five thousand, ninety-three".