261433400616 has 384 divisors, whose sum is σ = 797220403200. Its totient is φ = 77007490560.

The previous prime is 261433400603. The next prime is 261433400623. The reversal of 261433400616 is 616004334162.

261433400616 is a `hidden beast` number, since 2 + 6 + 1 + 4 + 3 + 34 + 0 + 0 + 616 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 351861541 + ... + 351862283.

It is an arithmetic number, because the mean of its divisors is an integer number (2076094800).

Almost surely, 2^261433400616 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 261433400616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (398610201600).

261433400616 is an abundant number, since it is smaller than the sum of its proper divisors (535787002584).

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

261433400616 is a wasteful number, since it uses less digits than its factorization.

261433400616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1061 (or 1054 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

Adding to 261433400616 its reverse (616004334162), we get a palindrome (877437734778).

The spelling of 261433400616 in words is "two hundred sixty-one billion, four hundred thirty-three million, four hundred thousand, six hundred sixteen".