261493428224 has 312 divisors, whose sum is σ = 652327046208. Its totient is φ = 104230748160.

The previous prime is 261493428181. The next prime is 261493428271. The reversal of 261493428224 is 422824394162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 170798339 + ... + 170799869.

Almost surely, 2^261493428224 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261493428224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326163523104).

261493428224 is an abundant number, since it is smaller than the sum of its proper divisors (390833617984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261493428224 is a wasteful number, since it uses less digits than its factorization.

261493428224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1629 (or 1600 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 47.

The spelling of 261493428224 in words is "two hundred sixty-one billion, four hundred ninety-three million, four hundred twenty-eight thousand, two hundred twenty-four".