821444745 has 16 divisors (see below), whose sum is σ = 1433794752. Its totient is φ = 398276160.

The previous prime is 821444719. The next prime is 821444759. The reversal of 821444745 is 547444128.

It is not a de Polignac number, because 821444745 - 2⁸ = 821444489 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2489062 + ... + 2489391.

It is an arithmetic number, because the mean of its divisors is an integer number (89612172).

Almost surely, 2^821444745 is an apocalyptic number.

It is an amenable number.

821444745 is a deficient number, since it is larger than the sum of its proper divisors (612350007).

821444745 is a wasteful number, since it uses less digits than its factorization.

821444745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4978472.

The product of its digits is 143360, while the sum is 39.

The square root of 821444745 is about 28660.8573667991. The cubic root of 821444745 is about 936.5395418687.

The spelling of 821444745 in words is "eight hundred twenty-one million, four hundred forty-four thousand, seven hundred forty-five".