21461524217 has 16 divisors (see below), whose sum is σ = 26113756032. Its totient is φ = 17217826560.

The previous prime is 21461524187. The next prime is 21461524243. The reversal of 21461524217 is 71242516412.

It is a cyclic number.

It is not a de Polignac number, because 21461524217 - 2⁸ = 21461523961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21461524247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 476663 + ... + 519740.

It is an arithmetic number, because the mean of its divisors is an integer number (1632109752).

Almost surely, 2^21461524217 is an apocalyptic number.

It is an amenable number.

21461524217 is a deficient number, since it is larger than the sum of its proper divisors (4652231815).

21461524217 is a wasteful number, since it uses less digits than its factorization.

21461524217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996608.

The product of its digits is 26880, while the sum is 35.

It can be divided in two parts, 214615 and 24217, that added together give a palindrome (238832).

The spelling of 21461524217 in words is "twenty-one billion, four hundred sixty-one million, five hundred twenty-four thousand, two hundred seventeen".