21735091945 has 16 divisors (see below), whose sum is σ = 30416457600. Its totient is φ = 14904061872.

The previous prime is 21735091901. The next prime is 21735091949. The reversal of 21735091945 is 54919053712.

It is not a de Polignac number, because 21735091945 - 2⁷ = 21735091817 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21735091895 and 21735091904.

It is not an unprimeable number, because it can be changed into a prime (21735091949) 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, 6335047 + ... + 6338476.

It is an arithmetic number, because the mean of its divisors is an integer number (1901028600).

Almost surely, 2^21735091945 is an apocalyptic number.

It is an amenable number.

21735091945 is a deficient number, since it is larger than the sum of its proper divisors (8681365655).

21735091945 is an equidigital number, since it uses as much as digits as its factorization.

21735091945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12673549 (or 12673535 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 46.

The spelling of 21735091945 in words is "twenty-one billion, seven hundred thirty-five million, ninety-one thousand, nine hundred forty-five".