21540770446 has 8 divisors (see below), whose sum is σ = 34796629224. Its totient is φ = 9941894040.

The previous prime is 21540770441. The next prime is 21540770491. The reversal of 21540770446 is 64407704512.

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

It is a junction number, because it is equal to n+sod(n) for n = 21540770399 and 21540770408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21540770441) 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, 414245560 + ... + 414245611.

It is an arithmetic number, because the mean of its divisors is an integer number (4349578653).

Almost surely, 2^21540770446 is an apocalyptic number.

21540770446 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21540770446 is a deficient number, since it is larger than the sum of its proper divisors (13255858778).

21540770446 is a wasteful number, since it uses less digits than its factorization.

21540770446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828491186.

The product of its (nonzero) digits is 188160, while the sum is 40.

The spelling of 21540770446 in words is "twenty-one billion, five hundred forty million, seven hundred seventy thousand, four hundred forty-six".