1391036421 has 4 divisors (see below), whose sum is σ = 1854715232. Its totient is φ = 927357612.

The previous prime is 1391036411. The next prime is 1391036443. The reversal of 1391036421 is 1246301931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1391036421 - 2¹⁷ = 1390905349 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 (1391036411) 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, 231839401 + ... + 231839406.

It is an arithmetic number, because the mean of its divisors is an integer number (463678808).

Almost surely, 2^1391036421 is an apocalyptic number.

It is an amenable number.

1391036421 is a deficient number, since it is larger than the sum of its proper divisors (463678811).

1391036421 is an equidigital number, since it uses as much as digits as its factorization.

1391036421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463678810.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 1391036421 is about 37296.6006627950. The cubic root of 1391036421 is about 1116.2963388413.

The spelling of 1391036421 in words is "one billion, three hundred ninety-one million, thirty-six thousand, four hundred twenty-one".