1561213443 has 8 divisors (see below), whose sum is σ = 2115743056. Its totient is φ = 1023746400.

The previous prime is 1561213441. The next prime is 1561213447. The reversal of 1561213443 is 3443121651.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1561213443 - 2¹ = 1561213441 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1561213443.

It is not an unprimeable number, because it can be changed into a prime (1561213441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4265428 + ... + 4265793.

It is an arithmetic number, because the mean of its divisors is an integer number (264467882).

Almost surely, 2^1561213443 is an apocalyptic number.

1561213443 is a deficient number, since it is larger than the sum of its proper divisors (554529613).

1561213443 is an equidigital number, since it uses as much as digits as its factorization.

1561213443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8531285.

The product of its digits is 8640, while the sum is 30.

The square root of 1561213443 is about 39512.1935989385. The cubic root of 1561213443 is about 1160.0786319567.

The spelling of 1561213443 in words is "one billion, five hundred sixty-one million, two hundred thirteen thousand, four hundred forty-three".