821252148491 has 16 divisors (see below), whose sum is σ = 873310291200. Its totient is φ = 770082300000.

The previous prime is 821252148469. The next prime is 821252148523. The reversal of 821252148491 is 194841252128.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-821252148491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (821252148461) 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, 6172850 + ... + 6304488.

It is an arithmetic number, because the mean of its divisors is an integer number (54581893200).

Almost surely, 2^821252148491 is an apocalyptic number.

821252148491 is a deficient number, since it is larger than the sum of its proper divisors (52058142709).

821252148491 is a wasteful number, since it uses less digits than its factorization.

821252148491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135010.

The product of its digits is 368640, while the sum is 47.

The spelling of 821252148491 in words is "eight hundred twenty-one billion, two hundred fifty-two million, one hundred forty-eight thousand, four hundred ninety-one".