1266365645 has 4 divisors (see below), whose sum is σ = 1519638780. Its totient is φ = 1013092512.

The previous prime is 1266365629. The next prime is 1266365657. The reversal of 1266365645 is 5465636621.

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 215179561 + 1051186084 = 14669^2 + 32422^2 .

It is a cyclic number.

It is not a de Polignac number, because 1266365645 - 2⁴ = 1266365629 is a prime.

It is a super-3 number, since 3×1266365645³ (a number of 28 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1266365596 and 1266365605.

It is a congruent number.

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, 126636560 + ... + 126636569.

It is an arithmetic number, because the mean of its divisors is an integer number (379909695).

Almost surely, 2^1266365645 is an apocalyptic number.

It is an amenable number.

1266365645 is a deficient number, since it is larger than the sum of its proper divisors (253273135).

1266365645 is an equidigital number, since it uses as much as digits as its factorization.

1266365645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253273134.

The product of its digits is 777600, while the sum is 44.

The square root of 1266365645 is about 35586.0315994914. The cubic root of 1266365645 is about 1081.8981380528.

The spelling of 1266365645 in words is "one billion, two hundred sixty-six million, three hundred sixty-five thousand, six hundred forty-five".