1066636561 has 8 divisors (see below), whose sum is σ = 1101464064. Its totient is φ = 1031835360.

The previous prime is 1066636553. The next prime is 1066636601. The reversal of 1066636561 is 1656366601.

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

It is a cyclic number.

It is not a de Polignac number, because 1066636561 - 2³ = 1066636553 is a prime.

It is a super-2 number, since 2×1066636561² = 2275427106523813442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1066636511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107565 + ... + 117061.

It is an arithmetic number, because the mean of its divisors is an integer number (137683008).

Almost surely, 2^1066636561 is an apocalyptic number.

It is an amenable number.

1066636561 is a deficient number, since it is larger than the sum of its proper divisors (34827503).

1066636561 is an equidigital number, since it uses as much as digits as its factorization.

1066636561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13151.

The product of its (nonzero) digits is 116640, while the sum is 40.

The square root of 1066636561 is about 32659.4023368463. The cubic root of 1066636561 is about 1021.7362971608.

The spelling of 1066636561 in words is "one billion, sixty-six million, six hundred thirty-six thousand, five hundred sixty-one".