1645650243241 has 9 divisors (see below), whose sum is σ = 1668597159909. Its totient is φ = 1623014725536.

The previous prime is 1645650243239. The next prime is 1645650243283. The reversal of 1645650243241 is 1423420565461.

The square root of 1645650243241 is 1282829.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 118596895641 + 1527053347600 = 344379^2 + 1235740^2 .

It is not a de Polignac number, because 1645650243241 - 2¹ = 1645650243239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1645650241241) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 93637731 + ... + 93655303.

Almost surely, 2^{1645650243241} is an apocalyptic number.

1645650243241 is the 1282829-th square number.

1645650243241 is the 641415-th centered octagonal number.

It is an amenable number.

1645650243241 is a deficient number, since it is larger than the sum of its proper divisors (22946916668).

1645650243241 is an frugal number, since it uses more digits than its factorization.

1645650243241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35292 (or 17646 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 43.

The spelling of 1645650243241 in words is "one trillion, six hundred forty-five billion, six hundred fifty million, two hundred forty-three thousand, two hundred forty-one".