2021997847 has 4 divisors (see below), whose sum is σ = 2087223616. Its totient is φ = 1956772080.

The previous prime is 2021997839. The next prime is 2021997869. The reversal of 2021997847 is 7487991202.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 2021997847 - 2³ = 2021997839 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2021997847.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021997947) 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, 32612838 + ... + 32612899.

It is an arithmetic number, because the mean of its divisors is an integer number (521805904).

Almost surely, 2^2021997847 is an apocalyptic number.

2021997847 is a deficient number, since it is larger than the sum of its proper divisors (65225769).

2021997847 is an equidigital number, since it uses as much as digits as its factorization.

2021997847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65225768.

The product of its (nonzero) digits is 508032, while the sum is 49.

The square root of 2021997847 is about 44966.6303718658. The cubic root of 2021997847 is about 1264.5234754188.

The spelling of 2021997847 in words is "two billion, twenty-one million, nine hundred ninety-seven thousand, eight hundred forty-seven".