1640267 has 2 divisors, whose sum is σ = 1640268. Its totient is φ = 1640266.

The previous prime is 1640263. The next prime is 1640273. The reversal of 1640267 is 7620461.

It is a weak prime.

It is an emirp because it is prime and its reverse (7620461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1640267 - 2² = 1640263 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1640263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820133 + 820134.

It is an arithmetic number, because the mean of its divisors is an integer number (820134).

2^1640267 is an apocalyptic number.

1640267 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640267 is an equidigital number, since it uses as much as digits as its factorization.

1640267 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 1640267 is about 1280.7290892300. The cubic root of 1640267 is about 117.9337701692.

The spelling of 1640267 in words is "one million, six hundred forty thousand, two hundred sixty-seven".