21978030290394 has 32 divisors (see below), whose sum is σ = 44277887376576. Its totient is φ = 7272374664320.

The previous prime is 21978030290393. The next prime is 21978030290449. The reversal of 21978030290394 is 49309203087912.

It is not an unprimeable number, because it can be changed into a prime (21978030290393) 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, 40259224 + ... + 40801484.

It is an arithmetic number, because the mean of its divisors is an integer number (1383683980518).

Almost surely, 2^{21978030290394} is an apocalyptic number.

21978030290394 is an abundant number, since it is smaller than the sum of its proper divisors (22299857086182).

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

21978030290394 is a wasteful number, since it uses less digits than its factorization.

21978030290394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 591710.

The product of its (nonzero) digits is 5878656, while the sum is 57.

The spelling of 21978030290394 in words is "twenty-one trillion, nine hundred seventy-eight billion, thirty million, two hundred ninety thousand, three hundred ninety-four".