261950578 has 4 divisors (see below), whose sum is σ = 392925870. Its totient is φ = 130975288.

The previous prime is 261950543. The next prime is 261950593. The reversal of 261950578 is 875059162.

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., 233998209 + 27952369 = 15297^2 + 5287^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65487643 + ... + 65487646.

Almost surely, 2^261950578 is an apocalyptic number.

261950578 is a deficient number, since it is larger than the sum of its proper divisors (130975292).

261950578 is a wasteful number, since it uses less digits than its factorization.

261950578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130975291.

The product of its (nonzero) digits is 151200, while the sum is 43.

The square root of 261950578 is about 16184.8873335590. The cubic root of 261950578 is about 639.8425540434.

The spelling of 261950578 in words is "two hundred sixty-one million, nine hundred fifty thousand, five hundred seventy-eight".