1640524649 has 2 divisors, whose sum is σ = 1640524650. Its totient is φ = 1640524648.

The previous prime is 1640524603. The next prime is 1640524661. The reversal of 1640524649 is 9464250461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1495755625 + 144769024 = 38675^2 + 12032^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640524649 is a prime.

It is a super-2 number, since 2×1640524649² = 5382642247953146402, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1640524549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820262324 + 820262325.

It is an arithmetic number, because the mean of its divisors is an integer number (820262325).

Almost surely, 2^1640524649 is an apocalyptic number.

It is an amenable number.

1640524649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640524649 is an equidigital number, since it uses as much as digits as its factorization.

1640524649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 207360, while the sum is 41.

The square root of 1640524649 is about 40503.3905864682. The cubic root of 1640524649 is about 1179.3994475890.

The spelling of 1640524649 in words is "one billion, six hundred forty million, five hundred twenty-four thousand, six hundred forty-nine".