21955227478 has 8 divisors (see below), whose sum is σ = 32948627472. Its totient is φ = 10972351656.

The previous prime is 21955227467. The next prime is 21955227487. The reversal of 21955227478 is 87472255912.

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

It is a super-2 number, since 2×21955227478² (a number of 21 digits) contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 2625825 + ... + 2634172.

It is an arithmetic number, because the mean of its divisors is an integer number (4118578434).

Almost surely, 2^21955227478 is an apocalyptic number.

21955227478 is a deficient number, since it is larger than the sum of its proper divisors (10993399994).

21955227478 is a wasteful number, since it uses less digits than its factorization.

21955227478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5262086.

The product of its digits is 2822400, while the sum is 52.

The spelling of 21955227478 in words is "twenty-one billion, nine hundred fifty-five million, two hundred twenty-seven thousand, four hundred seventy-eight".