21019845694 has 8 divisors (see below), whose sum is σ = 31537510560. Its totient is φ = 10507342176.

The previous prime is 21019845661. The next prime is 21019845727. The reversal of 21019845694 is 49654891012.

It is an interprime number because it is at equal distance from previous prime (21019845661) and next prime (21019845727).

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

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 1280139 + ... + 1296454.

It is an arithmetic number, because the mean of its divisors is an integer number (3942188820).

Almost surely, 2^21019845694 is an apocalyptic number.

21019845694 is a deficient number, since it is larger than the sum of its proper divisors (10517664866).

21019845694 is a wasteful number, since it uses less digits than its factorization.

21019845694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2580674.

The product of its (nonzero) digits is 622080, while the sum is 49.

The spelling of 21019845694 in words is "twenty-one billion, nineteen million, eight hundred forty-five thousand, six hundred ninety-four".