21420478334 has 4 divisors (see below), whose sum is σ = 32130717504. Its totient is φ = 10710239166.

The previous prime is 21420478273. The next prime is 21420478351. The reversal of 21420478334 is 43387402412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5355119582 + ... + 5355119585.

It is an arithmetic number, because the mean of its divisors is an integer number (8032679376).

Almost surely, 2^21420478334 is an apocalyptic number.

21420478334 is a deficient number, since it is larger than the sum of its proper divisors (10710239170).

21420478334 is a wasteful number, since it uses less digits than its factorization.

21420478334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10710239169.

The product of its (nonzero) digits is 129024, while the sum is 38.

The spelling of 21420478334 in words is "twenty-one billion, four hundred twenty million, four hundred seventy-eight thousand, three hundred thirty-four".