21101768 has 32 divisors (see below), whose sum is σ = 40642560. Its totient is φ = 10268160.

The previous prime is 21101767. The next prime is 21101771. The reversal of 21101768 is 86710112.

It is a super-2 number, since 2×21101768² = 890569225451648, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21101767) 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, 54905 + ... + 55287.

It is an arithmetic number, because the mean of its divisors is an integer number (1270080).

Almost surely, 2^21101768 is an apocalyptic number.

It is an amenable number.

21101768 is a deficient number, since it is larger than the sum of its proper divisors (19540792).

21101768 is a wasteful number, since it uses less digits than its factorization.

21101768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557 (or 553 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 26.

The square root of 21101768 is about 4593.6660740633. Note that the first 3 decimals coincide. The cubic root of 21101768 is about 276.3373666323.

The spelling of 21101768 in words is "twenty-one million, one hundred one thousand, seven hundred sixty-eight".