2400402661 has 4 divisors (see below), whose sum is σ = 2400707500. Its totient is φ = 2400097824.

The previous prime is 2400402637. The next prime is 2400402671. The reversal of 2400402661 is 1662040042.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 137592900 + 2262809761 = 11730^2 + 47569^2 .

It is a cyclic number.

It is not a de Polignac number, because 2400402661 - 2¹⁹ = 2399878373 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 (2400402611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140286 + ... + 156463.

It is an arithmetic number, because the mean of its divisors is an integer number (600176875).

Almost surely, 2^2400402661 is an apocalyptic number.

It is an amenable number.

2400402661 is a deficient number, since it is larger than the sum of its proper divisors (304839).

2400402661 is an equidigital number, since it uses as much as digits as its factorization.

2400402661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304838.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 2400402661 is about 48993.9043249260. The cubic root of 2400402661 is about 1338.9407722387.

The spelling of 2400402661 in words is "two billion, four hundred million, four hundred two thousand, six hundred sixty-one".