21091462441 has 9 divisors (see below), whose sum is σ = 24536149149. Its totient is φ = 18077525004.

The previous prime is 21091462391. The next prime is 21091462451. The reversal of 21091462441 is 14426419012.

It is a happy number.

The square root of 21091462441 is 145229.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 21091462441 - 2⁹ = 21091461929 is a prime.

It is a super-2 number, since 2×21091462441² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21091462397 and 21091462406.

It is not an unprimeable number, because it can be changed into a prime (21091462451) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1006230 + ... + 1026976.

Almost surely, 2^21091462441 is an apocalyptic number.

21091462441 is the 145229-th square number.

21091462441 is the 72615-th centered octagonal number.

It is an amenable number.

21091462441 is a deficient number, since it is larger than the sum of its proper divisors (3444686708).

21091462441 is an frugal number, since it uses more digits than its factorization.

21091462441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41508 (or 20754 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 34.

The spelling of 21091462441 in words is "twenty-one billion, ninety-one million, four hundred sixty-two thousand, four hundred forty-one".