19995967 has 2 divisors, whose sum is σ = 19995968. Its totient is φ = 19995966.

The previous prime is 19995959. The next prime is 19995973. The reversal of 19995967 is 76959991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19995967 - 2³ = 19995959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19995667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9997983 + 9997984.

It is an arithmetic number, because the mean of its divisors is an integer number (9997984).

Almost surely, 2^19995967 is an apocalyptic number.

19995967 is a deficient number, since it is larger than the sum of its proper divisors (1).

19995967 is an equidigital number, since it uses as much as digits as its factorization.

19995967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1377810, while the sum is 55.

The square root of 19995967 is about 4471.6850291585. The cubic root of 19995967 is about 271.4235150225.

The spelling of 19995967 in words is "nineteen million, nine hundred ninety-five thousand, nine hundred sixty-seven".