21471804378 has 32 divisors (see below), whose sum is σ = 47726280000. Its totient is φ = 7155594288.

The previous prime is 21471804377. The next prime is 21471804391. The reversal of 21471804378 is 87340817412.

It is a super-2 number, since 2×21471804378² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21471804371) 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, 198373 + ... + 286871.

It is an arithmetic number, because the mean of its divisors is an integer number (1491446250).

Almost surely, 2^21471804378 is an apocalyptic number.

21471804378 is an abundant number, since it is smaller than the sum of its proper divisors (26254475622).

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

21471804378 is a wasteful number, since it uses less digits than its factorization.

21471804378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93003 (or 92997 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 45.

The spelling of 21471804378 in words is "twenty-one billion, four hundred seventy-one million, eight hundred four thousand, three hundred seventy-eight".