1640880493249 has 2 divisors, whose sum is σ = 1640880493250. Its totient is φ = 1640880493248.

The previous prime is 1640880493247. The next prime is 1640880493309. The reversal of 1640880493249 is 9423940880461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1640879017024 + 1476225 = 1280968^2 + 1215^2 .

It is an emirp because it is prime and its reverse (9423940880461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1640880493249 - 2¹ = 1640880493247 is a prime.

Together with 1640880493247, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1640880493193 and 1640880493202.

It is not a weakly prime, because it can be changed into another prime (1640880493247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820440246624 + 820440246625.

It is an arithmetic number, because the mean of its divisors is an integer number (820440246625).

Almost surely, 2^{1640880493249} is an apocalyptic number.

It is an amenable number.

1640880493249 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640880493249 is an equidigital number, since it uses as much as digits as its factorization.

1640880493249 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11943936, while the sum is 58.

The spelling of 1640880493249 in words is "one trillion, six hundred forty billion, eight hundred eighty million, four hundred ninety-three thousand, two hundred forty-nine".