261594994 has 4 divisors (see below), whose sum is σ = 392392494. Its totient is φ = 130797496.

The previous prime is 261594973. The next prime is 261595003. The reversal of 261594994 is 499495162.

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., 252969025 + 8625969 = 15905^2 + 2937^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

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, 65398747 + ... + 65398750.

Almost surely, 2^261594994 is an apocalyptic number.

261594994 is a deficient number, since it is larger than the sum of its proper divisors (130797500).

261594994 is a wasteful number, since it uses less digits than its factorization.

261594994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130797499.

The product of its digits is 699840, while the sum is 49.

The square root of 261594994 is about 16173.8985405498. The cubic root of 261594994 is about 639.5529055126.

The spelling of 261594994 in words is "two hundred sixty-one million, five hundred ninety-four thousand, nine hundred ninety-four".