1240221404391 has 4 divisors (see below), whose sum is σ = 1653628539192. Its totient is φ = 826814269592.

The previous prime is 1240221404381. The next prime is 1240221404399. The reversal of 1240221404391 is 1934041220421.

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 1240221404391 - 2¹³ = 1240221396199 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1240221404399) 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, 206703567396 + ... + 206703567401.

It is an arithmetic number, because the mean of its divisors is an integer number (413407134798).

Almost surely, 2^{1240221404391} is an apocalyptic number.

1240221404391 is a deficient number, since it is larger than the sum of its proper divisors (413407134801).

1240221404391 is an equidigital number, since it uses as much as digits as its factorization.

1240221404391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413407134800.

The product of its (nonzero) digits is 13824, while the sum is 33.

The spelling of 1240221404391 in words is "one trillion, two hundred forty billion, two hundred twenty-one million, four hundred four thousand, three hundred ninety-one".