1397981269 has 4 divisors (see below), whose sum is σ = 1398057696. Its totient is φ = 1397904844.

The previous prime is 1397981261. The next prime is 1397981293. The reversal of 1397981269 is 9621897931.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9621897931 = 463 ⋅20781637.

It is a cyclic number.

It is not a de Polignac number, because 1397981269 - 2³ = 1397981261 is a prime.

It is a super-2 number, since 2×1397981269² = 3908703256949700722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1397981261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7272 + ... + 53374.

It is an arithmetic number, because the mean of its divisors is an integer number (349514424).

Almost surely, 2^1397981269 is an apocalyptic number.

It is an amenable number.

1397981269 is a deficient number, since it is larger than the sum of its proper divisors (76427).

1397981269 is an equidigital number, since it uses as much as digits as its factorization.

1397981269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76426.

The product of its digits is 1469664, while the sum is 55.

The square root of 1397981269 is about 37389.5877083447. The cubic root of 1397981269 is about 1118.1509853231.

The spelling of 1397981269 in words is "one billion, three hundred ninety-seven million, nine hundred eighty-one thousand, two hundred sixty-nine".