21801348894 has 32 divisors (see below), whose sum is σ = 47267748864. Its totient is φ = 6663679200.

The previous prime is 21801348871. The next prime is 21801348917. The reversal of 21801348894 is 49884310812.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21801348871) and next prime (21801348917).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 913734 + ... + 937289.

It is an arithmetic number, because the mean of its divisors is an integer number (1477117152).

Almost surely, 2^21801348894 is an apocalyptic number.

21801348894 is an abundant number, since it is smaller than the sum of its proper divisors (25466399970).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21801348894 is a wasteful number, since it uses less digits than its factorization.

21801348894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1851192.

The product of its (nonzero) digits is 442368, while the sum is 48.

The spelling of 21801348894 in words is "twenty-one billion, eight hundred one million, three hundred forty-eight thousand, eight hundred ninety-four".