661101671 has 8 divisors (see below), whose sum is σ = 691637184. Its totient is φ = 631252480.

The previous prime is 661101659. The next prime is 661101697. The reversal of 661101671 is 176101166.

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 661101671 - 2¹⁴ = 661085287 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 (661101601) 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, 169610 + ... + 173463.

It is an arithmetic number, because the mean of its divisors is an integer number (86454648).

Almost surely, 2^661101671 is an apocalyptic number.

661101671 is a deficient number, since it is larger than the sum of its proper divisors (30535513).

661101671 is a wasteful number, since it uses less digits than its factorization.

661101671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343161.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 661101671 is about 25711.8974601253. The cubic root of 661101671 is about 871.1429339276.

The spelling of 661101671 in words is "six hundred sixty-one million, one hundred one thousand, six hundred seventy-one".