16425991 has 2 divisors, whose sum is σ = 16425992. Its totient is φ = 16425990.

The previous prime is 16425971. The next prime is 16426009. The reversal of 16425991 is 19952461.

16425991 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 (19952461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16425991 - 2¹⁷ = 16294919 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16425991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16425971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8212995 + 8212996.

It is an arithmetic number, because the mean of its divisors is an integer number (8212996).

Almost surely, 2^16425991 is an apocalyptic number.

16425991 is a deficient number, since it is larger than the sum of its proper divisors (1).

16425991 is an equidigital number, since it uses as much as digits as its factorization.

16425991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19440, while the sum is 37.

The square root of 16425991 is about 4052.8990858397. The cubic root of 16425991 is about 254.2009641913.

The spelling of 16425991 in words is "sixteen million, four hundred twenty-five thousand, nine hundred ninety-one".