1649856623 has 2 divisors, whose sum is σ = 1649856624. Its totient is φ = 1649856622.

The previous prime is 1649856617. The next prime is 1649856643. The reversal of 1649856623 is 3266589461.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1649856623 - 2¹² = 1649852527 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1649856643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 824928311 + 824928312.

It is an arithmetic number, because the mean of its divisors is an integer number (824928312).

Almost surely, 2^1649856623 is an apocalyptic number.

1649856623 is a deficient number, since it is larger than the sum of its proper divisors (1).

1649856623 is an equidigital number, since it uses as much as digits as its factorization.

1649856623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 50.

The square root of 1649856623 is about 40618.4271359687. The cubic root of 1649856623 is about 1181.6315224679.

The spelling of 1649856623 in words is "one billion, six hundred forty-nine million, eight hundred fifty-six thousand, six hundred twenty-three".