1066615813 has 4 divisors (see below), whose sum is σ = 1082535520. Its totient is φ = 1050696108.

The previous prime is 1066615801. The next prime is 1066615859. The reversal of 1066615813 is 3185166601.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1066615813 - 2²¹ = 1064518661 is a prime.

It is a super-2 number, since 2×1066615813² = 2275338585083301938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1066615013) 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, 7959753 + ... + 7959886.

It is an arithmetic number, because the mean of its divisors is an integer number (270633880).

Almost surely, 2^1066615813 is an apocalyptic number.

It is an amenable number.

1066615813 is a deficient number, since it is larger than the sum of its proper divisors (15919707).

1066615813 is an equidigital number, since it uses as much as digits as its factorization.

1066615813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15919706.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 1066615813 is about 32659.0846932366. The cubic root of 1066615813 is about 1021.7296722482.

The spelling of 1066615813 in words is "one billion, sixty-six million, six hundred fifteen thousand, eight hundred thirteen".