261650022400 has 384 divisors, whose sum is σ = 709917062400. Its totient is φ = 95079628800.

The previous prime is 261650022373. The next prime is 261650022401. The reversal of 261650022400 is 4220056162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261650022401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 841318245 + ... + 841318555.

It is an arithmetic number, because the mean of its divisors is an integer number (1848742350).

Almost surely, 2^261650022400 is an apocalyptic number.

261650022400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261650022400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (354958531200).

261650022400 is an abundant number, since it is smaller than the sum of its proper divisors (448267040000).

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

261650022400 is an equidigital number, since it uses as much as digits as its factorization.

261650022400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443 (or 410 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

Adding to 261650022400 its reverse (4220056162), we get a palindrome (265870078562).

The spelling of 261650022400 in words is "two hundred sixty-one billion, six hundred fifty million, twenty-two thousand, four hundred".