11439267821 has 2 divisors, whose sum is σ = 11439267822. Its totient is φ = 11439267820.

The previous prime is 11439267817. The next prime is 11439267883. The reversal of 11439267821 is 12876293411.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11395562500 + 43705321 = 106750^2 + 6611^2 .

It is a cyclic number.

It is not a de Polignac number, because 11439267821 - 2² = 11439267817 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11439264821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5719633910 + 5719633911.

It is an arithmetic number, because the mean of its divisors is an integer number (5719633911).

Almost surely, 2^11439267821 is an apocalyptic number.

It is an amenable number.

11439267821 is a deficient number, since it is larger than the sum of its proper divisors (1).

11439267821 is an equidigital number, since it uses as much as digits as its factorization.

11439267821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 44.

The spelling of 11439267821 in words is "eleven billion, four hundred thirty-nine million, two hundred sixty-seven thousand, eight hundred twenty-one".