21290346018 has 80 divisors (see below), whose sum is σ = 49005418176. Its totient is φ = 6904789920.

The previous prime is 21290345963. The next prime is 21290346031. The reversal of 21290346018 is 81064309212.

21290346018 is a `hidden beast` number, since 2 + 12 + 9 + 0 + 34 + 601 + 8 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1826248 + ... + 1837868.

Almost surely, 2^21290346018 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21290346018, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24502709088).

21290346018 is an abundant number, since it is smaller than the sum of its proper divisors (27715072158).

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

21290346018 is a wasteful number, since it uses less digits than its factorization.

21290346018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11941 (or 11932 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 21290346018 in words is "twenty-one billion, two hundred ninety million, three hundred forty-six thousand, eighteen".