1401666647 has 2 divisors, whose sum is σ = 1401666648. Its totient is φ = 1401666646.

The previous prime is 1401666611. The next prime is 1401666719. The reversal of 1401666647 is 7466661041.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1401666647 - 2¹⁶ = 1401601111 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1401686647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 700833323 + 700833324.

It is an arithmetic number, because the mean of its divisors is an integer number (700833324).

Almost surely, 2^1401666647 is an apocalyptic number.

1401666647 is a deficient number, since it is larger than the sum of its proper divisors (1).

1401666647 is an equidigital number, since it uses as much as digits as its factorization.

1401666647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 1401666647 is about 37438.8387506878. The cubic root of 1401666647 is about 1119.1326849866.

The spelling of 1401666647 in words is "one billion, four hundred one million, six hundred sixty-six thousand, six hundred forty-seven".