16391825 has 12 divisors (see below), whose sum is σ = 21522060. Its totient is φ = 12341760.

The previous prime is 16391819. The next prime is 16391833. The reversal of 16391825 is 52819361.

16391825 = 430² + 431² + ... + 504².

It can be written as a sum of positive squares in 6 ways, for example, as 126736 + 16265089 = 356^2 + 4033^2 .

It is not a de Polignac number, because 16391825 - 2⁶ = 16391761 is a prime.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 18860 + ... + 19709.

It is an arithmetic number, because the mean of its divisors is an integer number (1793505).

Almost surely, 2^16391825 is an apocalyptic number.

It is an amenable number.

16391825 is a deficient number, since it is larger than the sum of its proper divisors (5130235).

16391825 is a wasteful number, since it uses less digits than its factorization.

16391825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38596 (or 38591 counting only the distinct ones).

The product of its digits is 12960, while the sum is 35.

The square root of 16391825 is about 4048.6818842680. The cubic root of 16391825 is about 254.0245961673.

The spelling of 16391825 in words is "sixteen million, three hundred ninety-one thousand, eight hundred twenty-five".