15783979 has 2 divisors, whose sum is σ = 15783980. Its totient is φ = 15783978.

The previous prime is 15783961. The next prime is 15783997. The reversal of 15783979 is 97938751.

15783979 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (15783997) it forms an Ormiston pair, because they use the same digits, order apart.

It is a balanced prime because it is at equal distance from previous prime (15783961) and next prime (15783997).

It is a cyclic number.

It is not a de Polignac number, because 15783979 - 2¹⁷ = 15652907 is a prime.

It is not a weakly prime, because it can be changed into another prime (15783919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7891989 + 7891990.

It is an arithmetic number, because the mean of its divisors is an integer number (7891990).

Almost surely, 2^15783979 is an apocalyptic number.

15783979 is a deficient number, since it is larger than the sum of its proper divisors (1).

15783979 is an equidigital number, since it uses as much as digits as its factorization.

15783979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 476280, while the sum is 49.

The square root of 15783979 is about 3972.9056117658. The cubic root of 15783979 is about 250.8450284892.

The spelling of 15783979 in words is "fifteen million, seven hundred eighty-three thousand, nine hundred seventy-nine".