1043643261 has 4 divisors (see below), whose sum is σ = 1391524352. Its totient is φ = 695762172.

The previous prime is 1043643247. The next prime is 1043643317. The reversal of 1043643261 is 1623463401.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1043643261 - 2¹⁸ = 1043381117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1043645261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173940541 + ... + 173940546.

It is an arithmetic number, because the mean of its divisors is an integer number (347881088).

Almost surely, 2^1043643261 is an apocalyptic number.

It is an amenable number.

1043643261 is a deficient number, since it is larger than the sum of its proper divisors (347881091).

1043643261 is an equidigital number, since it uses as much as digits as its factorization.

1043643261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347881090.

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 1043643261 is about 32305.4679737038. The cubic root of 1043643261 is about 1014.3411032589.

The spelling of 1043643261 in words is "one billion, forty-three million, six hundred forty-three thousand, two hundred sixty-one".