19667997 has 12 divisors (see below), whose sum is σ = 30080700. Its totient is φ = 12340608.

The previous prime is 19667993. The next prime is 19668001. The reversal of 19667997 is 79976691.

It is an interprime number because it is at equal distance from previous prime (19667993) and next prime (19668001).

It can be written as a sum of positive squares in 2 ways, for example, as 5447556 + 14220441 = 2334^2 + 3771^2 .

It is not a de Polignac number, because 19667997 - 2² = 19667993 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19667993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64122 + ... + 64427.

It is an arithmetic number, because the mean of its divisors is an integer number (2506725).

Almost surely, 2^19667997 is an apocalyptic number.

19667997 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

19667997 is a deficient number, since it is larger than the sum of its proper divisors (10412703).

19667997 is a wasteful number, since it uses less digits than its factorization.

19667997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128572 (or 128569 counting only the distinct ones).

The product of its digits is 1285956, while the sum is 54.

The square root of 19667997 is about 4434.8615536452. The cubic root of 19667997 is about 269.9313817397.

The spelling of 19667997 in words is "nineteen million, six hundred sixty-seven thousand, nine hundred ninety-seven".