261502993 has 4 divisors (see below), whose sum is σ = 276885540. Its totient is φ = 246120448.

The previous prime is 261502991. The next prime is 261503003. The reversal of 261502993 is 399205162.

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 241895809 + 19607184 = 15553^2 + 4428^2 .

It is a cyclic number.

It is not a de Polignac number, because 261502993 - 2¹ = 261502991 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261502991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7691248 + ... + 7691281.

It is an arithmetic number, because the mean of its divisors is an integer number (69221385).

Almost surely, 2^261502993 is an apocalyptic number.

It is an amenable number.

261502993 is a deficient number, since it is larger than the sum of its proper divisors (15382547).

261502993 is a wasteful number, since it uses less digits than its factorization.

261502993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15382546.

The product of its (nonzero) digits is 29160, while the sum is 37.

The square root of 261502993 is about 16171.0541709562. The cubic root of 261502993 is about 639.4779213993.

The spelling of 261502993 in words is "two hundred sixty-one million, five hundred two thousand, nine hundred ninety-three".