11001211661 has 8 divisors (see below), whose sum is σ = 12004633344. Its totient is φ = 9998341920.

The previous prime is 11001211607. The next prime is 11001211691. The reversal of 11001211661 is 16611210011.

It is a happy number.

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 11001211661 - 2¹⁰ = 11001210637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11001211691) 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, 95741 + ... + 176546.

It is an arithmetic number, because the mean of its divisors is an integer number (1500579168).

Almost surely, 2^11001211661 is an apocalyptic number.

11001211661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11001211661 is a deficient number, since it is larger than the sum of its proper divisors (1003421683).

11001211661 is a wasteful number, since it uses less digits than its factorization.

11001211661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275971.

The product of its (nonzero) digits is 72, while the sum is 20.

Adding to 11001211661 its reverse (16611210011), we get a palindrome (27612421672).

The spelling of 11001211661 in words is "eleven billion, one million, two hundred eleven thousand, six hundred sixty-one".