21939978350 has 48 divisors (see below), whose sum is σ = 41907692736. Its totient is φ = 8541648000.

The previous prime is 21939978329. The next prime is 21939978383. The reversal of 21939978350 is 5387993912.

It is a happy number.

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 23 ways as a sum of consecutive naturals, for example, 399560 + ... + 451140.

It is an arithmetic number, because the mean of its divisors is an integer number (873076932).

Almost surely, 2^21939978350 is an apocalyptic number.

21939978350 is a deficient number, since it is larger than the sum of its proper divisors (19967714386).

21939978350 is a wasteful number, since it uses less digits than its factorization.

21939978350 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51821 (or 51816 counting only the distinct ones).

The product of its (nonzero) digits is 3674160, while the sum is 56.

The spelling of 21939978350 in words is "twenty-one billion, nine hundred thirty-nine million, nine hundred seventy-eight thousand, three hundred fifty".