21074749245 has 24 divisors (see below), whose sum is σ = 39850435872. Its totient is φ = 10218060000.

The previous prime is 21074749243. The next prime is 21074749259. The reversal of 21074749245 is 54294747012.

It is not a de Polignac number, because 21074749245 - 2¹ = 21074749243 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21074749245.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21074749243) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21287131 + ... + 21288120.

It is an arithmetic number, because the mean of its divisors is an integer number (1660434828).

Almost surely, 2^21074749245 is an apocalyptic number.

It is an amenable number.

21074749245 is a deficient number, since it is larger than the sum of its proper divisors (18775686627).

21074749245 is a wasteful number, since it uses less digits than its factorization.

21074749245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42575273 (or 42575270 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 45.

The spelling of 21074749245 in words is "twenty-one billion, seventy-four million, seven hundred forty-nine thousand, two hundred forty-five".