2421101561 has 4 divisors (see below), whose sum is σ = 2421210612. Its totient is φ = 2420992512.

The previous prime is 2421101539. The next prime is 2421101659. The reversal of 2421101561 is 1651011242.

2421101561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1651011242 = 2 ⋅825505621.

It can be written as a sum of positive squares in 2 ways, for example, as 531025936 + 1890075625 = 23044^2 + 43475^2 .

It is a cyclic number.

It is not a de Polignac number, because 2421101561 - 2¹⁸ = 2420839417 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2421103561) 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, 7976 + ... + 70041.

It is an arithmetic number, because the mean of its divisors is an integer number (605302653).

Almost surely, 2^2421101561 is an apocalyptic number.

It is an amenable number.

2421101561 is a deficient number, since it is larger than the sum of its proper divisors (109051).

2421101561 is an equidigital number, since it uses as much as digits as its factorization.

2421101561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109050.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 2421101561 is about 49204.6904369898. The cubic root of 2421101561 is about 1342.7783670958.

The spelling of 2421101561 in words is "two billion, four hundred twenty-one million, one hundred one thousand, five hundred sixty-one".