101666521 has 8 divisors (see below), whose sum is σ = 111387744. Its totient is φ = 92025120.

The previous prime is 101666507. The next prime is 101666527. The reversal of 101666521 is 125666101.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 101666521 - 2⁷ = 101666393 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 101666521.

It is not an unprimeable number, because it can be changed into a prime (101666527) 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, 17271 + ... + 22396.

It is an arithmetic number, because the mean of its divisors is an integer number (13923468).

Almost surely, 2^101666521 is an apocalyptic number.

101666521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

101666521 is a deficient number, since it is larger than the sum of its proper divisors (9721223).

101666521 is a wasteful number, since it uses less digits than its factorization.

101666521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39911.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 101666521 is about 10082.9817514463. The cubic root of 101666521 is about 466.7231262189.

The spelling of 101666521 in words is "one hundred one million, six hundred sixty-six thousand, five hundred twenty-one".