261501242 has 8 divisors (see below), whose sum is σ = 415325556. Its totient is φ = 123059392.

The previous prime is 261501223. The next prime is 261501269. The reversal of 261501242 is 242105162.

It is a happy number.

It is a Cunningham number, because it is equal to 16171²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 261501241 + 1 = 16171^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3845573 + ... + 3845640.

Almost surely, 2^261501242 is an apocalyptic number.

261501242 is a deficient number, since it is larger than the sum of its proper divisors (153824314).

261501242 is a wasteful number, since it uses less digits than its factorization.

261501242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7691232.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 261501242 is about 16171.0000309195. Note that the first 4 decimals coincide. The cubic root of 261501242 is about 639.4764941010.

The spelling of 261501242 in words is "two hundred sixty-one million, five hundred one thousand, two hundred forty-two".