21878464126 has 16 divisors (see below), whose sum is σ = 34799817024. Its totient is φ = 10280438784.

The previous prime is 21878464103. The next prime is 21878464189. The reversal of 21878464126 is 62146487812.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21878464126.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 455190 + ... + 500953.

It is an arithmetic number, because the mean of its divisors is an integer number (2174988564).

Almost surely, 2^21878464126 is an apocalyptic number.

21878464126 is a deficient number, since it is larger than the sum of its proper divisors (12921352898).

21878464126 is a wasteful number, since it uses less digits than its factorization.

21878464126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 956835.

The product of its digits is 1032192, while the sum is 49.

The spelling of 21878464126 in words is "twenty-one billion, eight hundred seventy-eight million, four hundred sixty-four thousand, one hundred twenty-six".