1399504121 has 4 divisors (see below), whose sum is σ = 1399791744. Its totient is φ = 1399216500.

The previous prime is 1399504103. The next prime is 1399504163. The reversal of 1399504121 is 1214059931.

It is a happy number.

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: 1214059931 = 7 ⋅173437133.

It is a cyclic number.

It is not a de Polignac number, because 1399504121 - 2¹⁰ = 1399503097 is a prime.

It is a super-2 number, since 2×1399504121² = 3917223569391965282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1399504321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136385 + ... + 146286.

It is an arithmetic number, because the mean of its divisors is an integer number (349947936).

Almost surely, 2^1399504121 is an apocalyptic number.

It is an amenable number.

1399504121 is a deficient number, since it is larger than the sum of its proper divisors (287623).

1399504121 is an equidigital number, since it uses as much as digits as its factorization.

1399504121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287622.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 1399504121 is about 37409.9468189945. The cubic root of 1399504121 is about 1118.5568468761.

The spelling of 1399504121 in words is "one billion, three hundred ninety-nine million, five hundred four thousand, one hundred twenty-one".