1000013661 has 16 divisors (see below), whose sum is σ = 1568649600. Its totient is φ = 627459264.

The previous prime is 1000013591. The next prime is 1000013723. The reversal of 1000013661 is 1663100001.

1000013661 is a `hidden beast` number, since 1 + 0 + 0 + 0 + 0 + 1 + 3 + 661 = 666.

It is not a de Polignac number, because 1000013661 - 2¹³ = 1000005469 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000013561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1088881 + ... + 1089798.

It is an arithmetic number, because the mean of its divisors is an integer number (98040600).

Almost surely, 2^1000013661 is an apocalyptic number.

It is an amenable number.

1000013661 is a deficient number, since it is larger than the sum of its proper divisors (568635939).

1000013661 is a wasteful number, since it uses less digits than its factorization.

1000013661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2178705 (or 2178699 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 1000013661 is about 31622.9926003217. The cubic root of 1000013661 is about 1000.0045536459.

Adding to 1000013661 its reverse (1663100001), we get a palindrome (2663113662).

The spelling of 1000013661 in words is "one billion, thirteen thousand, six hundred sixty-one".