15321139 has 2 divisors, whose sum is σ = 15321140. Its totient is φ = 15321138.

The previous prime is 15321127. The next prime is 15321143. The reversal of 15321139 is 93112351.

15321139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (93112351) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15321139 - 2²³ = 6932531 is a prime.

It is equal to p₉₉₀₁₄₂ and since 15321139 and 990142 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (15321169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7660569 + 7660570.

It is an arithmetic number, because the mean of its divisors is an integer number (7660570).

Almost surely, 2^15321139 is an apocalyptic number.

15321139 is a deficient number, since it is larger than the sum of its proper divisors (1).

15321139 is an equidigital number, since it uses as much as digits as its factorization.

15321139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 810, while the sum is 25.

The square root of 15321139 is about 3914.2226559050. Note that the first 3 decimals coincide. The cubic root of 15321139 is about 248.3687877351.

The spelling of 15321139 in words is "fifteen million, three hundred twenty-one thousand, one hundred thirty-nine".