21394108833 has 16 divisors (see below), whose sum is σ = 29491531776. Its totient is φ = 13781146320.

The previous prime is 21394108817. The next prime is 21394108849. The reversal of 21394108833 is 33880149312.

It is an interprime number because it is at equal distance from previous prime (21394108817) and next prime (21394108849).

It is not a de Polignac number, because 21394108833 - 2⁴ = 21394108817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21394108733) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119085 + ... + 238682.

It is an arithmetic number, because the mean of its divisors is an integer number (1843220736).

Almost surely, 2^21394108833 is an apocalyptic number.

It is an amenable number.

21394108833 is a deficient number, since it is larger than the sum of its proper divisors (8097422943).

21394108833 is a wasteful number, since it uses less digits than its factorization.

21394108833 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358444.

The product of its (nonzero) digits is 124416, while the sum is 42.

The spelling of 21394108833 in words is "twenty-one billion, three hundred ninety-four million, one hundred eight thousand, eight hundred thirty-three".