21101669 has 8 divisors (see below), whose sum is σ = 22141440. Its totient is φ = 20084400.

The previous prime is 21101651. The next prime is 21101677. The reversal of 21101669 is 96610112.

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 21101669 - 2¹⁶ = 21036133 is a prime.

It is a super-2 number, since 2×21101669² = 890560869171122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3689 + ... + 7470.

It is an arithmetic number, because the mean of its divisors is an integer number (2767680).

Almost surely, 2^21101669 is an apocalyptic number.

It is an amenable number.

21101669 is a deficient number, since it is larger than the sum of its proper divisors (1039771).

21101669 is a wasteful number, since it uses less digits than its factorization.

21101669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11251.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 21101669 is about 4593.6552983436. The cubic root of 21101669 is about 276.3369344815.

The spelling of 21101669 in words is "twenty-one million, one hundred one thousand, six hundred sixty-nine".