661286527 has 4 divisors (see below), whose sum is σ = 721403496. Its totient is φ = 601169560.

The previous prime is 661286489. The next prime is 661286557. The reversal of 661286527 is 725682166.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 661286527 - 2²³ = 652897919 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661286557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30058468 + ... + 30058489.

It is an arithmetic number, because the mean of its divisors is an integer number (180350874).

Almost surely, 2^661286527 is an apocalyptic number.

661286527 is a deficient number, since it is larger than the sum of its proper divisors (60116969).

661286527 is a wasteful number, since it uses less digits than its factorization.

661286527 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60116968.

The product of its digits is 241920, while the sum is 43.

The square root of 661286527 is about 25715.4919649615. The cubic root of 661286527 is about 871.2241221411.

It can be divided in two parts, 6612 and 86527, that added together give a palindrome (93139).

The spelling of 661286527 in words is "six hundred sixty-one million, two hundred eighty-six thousand, five hundred twenty-seven".