21101616801 has 32 divisors (see below), whose sum is σ = 31887851520. Its totient is φ = 13788632592.

The previous prime is 21101616787. The next prime is 21101616859. The reversal of 21101616801 is 10861610112.

It is not a de Polignac number, because 21101616801 - 2⁶ = 21101616737 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21101614801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 247536 + ... + 321678.

It is an arithmetic number, because the mean of its divisors is an integer number (996495360).

Almost surely, 2^21101616801 is an apocalyptic number.

It is an amenable number.

21101616801 is a deficient number, since it is larger than the sum of its proper divisors (10786234719).

21101616801 is a wasteful number, since it uses less digits than its factorization.

21101616801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74362 (or 74356 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The spelling of 21101616801 in words is "twenty-one billion, one hundred one million, six hundred sixteen thousand, eight hundred one".