102117661 has 4 divisors (see below), whose sum is σ = 102729312. Its totient is φ = 101506012.

The previous prime is 102117641. The next prime is 102117679. The reversal of 102117661 is 166711201.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 166711201 = 8677 ⋅19213.

It is a cyclic number.

It is not a de Polignac number, because 102117661 - 2⁵ = 102117629 is a prime.

It is a super-2 number, since 2×102117661² = 20856033376221842, 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 (102117641) 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, 305575 + ... + 305908.

It is an arithmetic number, because the mean of its divisors is an integer number (25682328).

Almost surely, 2^102117661 is an apocalyptic number.

It is an amenable number.

102117661 is a deficient number, since it is larger than the sum of its proper divisors (611651).

102117661 is an equidigital number, since it uses as much as digits as its factorization.

102117661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611650.

The product of its (nonzero) digits is 504, while the sum is 25.

The square root of 102117661 is about 10105.3283469663. The cubic root of 102117661 is about 467.4124609465.

Adding to 102117661 its reverse (166711201), we get a palindrome (268828862).

The spelling of 102117661 in words is "one hundred two million, one hundred seventeen thousand, six hundred sixty-one".