21095222878 has 8 divisors (see below), whose sum is σ = 31684417200. Its totient is φ = 10533750480.

The previous prime is 21095222857. The next prime is 21095222879. The reversal of 21095222878 is 87822259012.

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

It is a super-4 number, since 4×21095222878⁴ (a number of 42 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21095222879) 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, 6928578 + ... + 6931621.

It is an arithmetic number, because the mean of its divisors is an integer number (3960552150).

Almost surely, 2^21095222878 is an apocalyptic number.

21095222878 is a deficient number, since it is larger than the sum of its proper divisors (10589194322).

21095222878 is a wasteful number, since it uses less digits than its factorization.

21095222878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13860962.

The product of its (nonzero) digits is 322560, while the sum is 46.

The spelling of 21095222878 in words is "twenty-one billion, ninety-five million, two hundred twenty-two thousand, eight hundred seventy-eight".