2181409937279 has 4 divisors (see below), whose sum is σ = 2182998729576. Its totient is φ = 2179821144984.

The previous prime is 2181409937263. The next prime is 2181409937293. The reversal of 2181409937279 is 9727399041812.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 2181409937279 - 2⁴ = 2181409937263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181409930279) 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, 794394089 + ... + 794396834.

It is an arithmetic number, because the mean of its divisors is an integer number (545749682394).

Almost surely, 2^{2181409937279} is an apocalyptic number.

2181409937279 is a deficient number, since it is larger than the sum of its proper divisors (1588792297).

2181409937279 is a wasteful number, since it uses less digits than its factorization.

2181409937279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1588792296.

The product of its (nonzero) digits is 13716864, while the sum is 62.

The spelling of 2181409937279 in words is "two trillion, one hundred eighty-one billion, four hundred nine million, nine hundred thirty-seven thousand, two hundred seventy-nine".