1902648661 has 2 divisors, whose sum is σ = 1902648662. Its totient is φ = 1902648660.

The previous prime is 1902648659. The next prime is 1902648679. The reversal of 1902648661 is 1668462091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1656001636 + 246647025 = 40694^2 + 15705^2 .

It is an emirp because it is prime and its reverse (1668462091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1902648661 - 2¹ = 1902648659 is a prime.

Together with 1902648659, 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 (1902648161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 951324330 + 951324331.

It is an arithmetic number, because the mean of its divisors is an integer number (951324331).

Almost surely, 2^1902648661 is an apocalyptic number.

It is an amenable number.

1902648661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1902648661 is an equidigital number, since it uses as much as digits as its factorization.

1902648661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 124416, while the sum is 43.

The square root of 1902648661 is about 43619.3610796857. The cubic root of 1902648661 is about 1239.1375942844.

The spelling of 1902648661 in words is "one billion, nine hundred two million, six hundred forty-eight thousand, six hundred sixty-one".