21245645470 has 64 divisors (see below), whose sum is σ = 45367382016. Its totient is φ = 7012298880.

The previous prime is 21245645419. The next prime is 21245645479. The reversal of 21245645470 is 7454654212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21245645479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 147759 + ... + 253621.

It is an arithmetic number, because the mean of its divisors is an integer number (708865344).

Almost surely, 2^21245645470 is an apocalyptic number.

21245645470 is an abundant number, since it is smaller than the sum of its proper divisors (24121736546).

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

21245645470 is a wasteful number, since it uses less digits than its factorization.

21245645470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105985.

The product of its (nonzero) digits is 268800, while the sum is 40.

The spelling of 21245645470 in words is "twenty-one billion, two hundred forty-five million, six hundred forty-five thousand, four hundred seventy".