261615434 has 4 divisors (see below), whose sum is σ = 392423154. Its totient is φ = 130807716.

The previous prime is 261615433. The next prime is 261615437. The reversal of 261615434 is 434516162.

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

It can be written as a sum of positive squares in only one way, i.e., 208369225 + 53246209 = 14435^2 + 7297^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 261615434.

It is not an unprimeable number, because it can be changed into a prime (261615433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65403857 + ... + 65403860.

Almost surely, 2^261615434 is an apocalyptic number.

261615434 is a deficient number, since it is larger than the sum of its proper divisors (130807720).

261615434 is a wasteful number, since it uses less digits than its factorization.

261615434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130807719.

The product of its digits is 17280, while the sum is 32.

The square root of 261615434 is about 16174.5304104941. The cubic root of 261615434 is about 639.5695624584.

The spelling of 261615434 in words is "two hundred sixty-one million, six hundred fifteen thousand, four hundred thirty-four".