1396338821 has 4 divisors (see below), whose sum is σ = 1396464000. Its totient is φ = 1396213644.

The previous prime is 1396338793. The next prime is 1396338841. The reversal of 1396338821 is 1288336931.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1288336931 = 7 ⋅184048133.

It is a cyclic number.

It is not a de Polignac number, because 1396338821 - 2¹⁴ = 1396322437 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 (1396338841) 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, 44021 + ... + 68778.

It is an arithmetic number, because the mean of its divisors is an integer number (349116000).

Almost surely, 2^1396338821 is an apocalyptic number.

It is an amenable number.

1396338821 is a deficient number, since it is larger than the sum of its proper divisors (125179).

1396338821 is a wasteful number, since it uses less digits than its factorization.

1396338821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125178.

The product of its digits is 186624, while the sum is 44.

The square root of 1396338821 is about 37367.6172775306. The cubic root of 1396338821 is about 1117.7129192395.

The spelling of 1396338821 in words is "one billion, three hundred ninety-six million, three hundred thirty-eight thousand, eight hundred twenty-one".