1066640623 has 2 divisors, whose sum is σ = 1066640624. Its totient is φ = 1066640622.

The previous prime is 1066640621. The next prime is 1066640629. The reversal of 1066640623 is 3260466601.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1066640623 - 2¹ = 1066640621 is a prime.

It is a super-2 number, since 2×1066640623² = 2275444437267656258, which contains 22 as substring.

Together with 1066640621, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1066640621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 533320311 + 533320312.

It is an arithmetic number, because the mean of its divisors is an integer number (533320312).

Almost surely, 2^1066640623 is an apocalyptic number.

1066640623 is a deficient number, since it is larger than the sum of its proper divisors (1).

1066640623 is an equidigital number, since it uses as much as digits as its factorization.

1066640623 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 1066640623 is about 32659.4645240855. The cubic root of 1066640623 is about 1021.7375941623.

The spelling of 1066640623 in words is "one billion, sixty-six million, six hundred forty thousand, six hundred twenty-three".