8661466777621 has 4 divisors (see below), whose sum is σ = 9898819174432. Its totient is φ = 7424114380812.

The previous prime is 8661466777609. The next prime is 8661466777637. The reversal of 8661466777621 is 1267776641668.

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 8661466777621 - 2¹³ = 8661466769429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8661466777681) 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, 618676198395 + ... + 618676198408.

It is an arithmetic number, because the mean of its divisors is an integer number (2474704793608).

Almost surely, 2^{8661466777621} is an apocalyptic number.

It is an amenable number.

8661466777621 is a deficient number, since it is larger than the sum of its proper divisors (1237352396811).

8661466777621 is a wasteful number, since it uses less digits than its factorization.

8661466777621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237352396810.

The product of its digits is 170698752, while the sum is 67.

The spelling of 8661466777621 in words is "eight trillion, six hundred sixty-one billion, four hundred sixty-six million, seven hundred seventy-seven thousand, six hundred twenty-one".