261066356 has 6 divisors (see below), whose sum is σ = 456866130. Its totient is φ = 130533176.

The previous prime is 261066343. The next prime is 261066389. The reversal of 261066356 is 653660162.

It can be written as a sum of positive squares in only one way, i.e., 187690000 + 73376356 = 13700^2 + 8566^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32633291 + ... + 32633298.

It is an arithmetic number, because the mean of its divisors is an integer number (76144355).

Almost surely, 2^261066356 is an apocalyptic number.

It is an amenable number.

261066356 is a deficient number, since it is larger than the sum of its proper divisors (195799774).

261066356 is a wasteful number, since it uses less digits than its factorization.

261066356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65266593 (or 65266591 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 261066356 is about 16157.5479575337. The cubic root of 261066356 is about 639.1218065819.

The spelling of 261066356 in words is "two hundred sixty-one million, sixty-six thousand, three hundred fifty-six".