21811390698 has 8 divisors (see below), whose sum is σ = 43622781408. Its totient is φ = 7270463564.

The previous prime is 21811390697. The next prime is 21811390703. The reversal of 21811390698 is 89609311812.

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

21811390698 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21811390693) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1817615886 + ... + 1817615897.

It is an arithmetic number, because the mean of its divisors is an integer number (5452847676).

Almost surely, 2^21811390698 is an apocalyptic number.

21811390698 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21811390698 is a wasteful number, since it uses less digits than its factorization.

21811390698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3635231788.

The product of its (nonzero) digits is 186624, while the sum is 48.

The spelling of 21811390698 in words is "twenty-one billion, eight hundred eleven million, three hundred ninety thousand, six hundred ninety-eight".