261769536 has 448 divisors, whose sum is σ = 994867200. Its totient is φ = 65691648.

The previous prime is 261769531. The next prime is 261769537. The reversal of 261769536 is 635967162.

It is a tau number, because it is divible by the number of its divisors (448).

It is a junction number, because it is equal to n+sod(n) for n = 261769491 and 261769500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261769531) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3906975 + ... + 3907041.

Almost surely, 2^261769536 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 261769536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (497433600).

261769536 is an abundant number, since it is smaller than the sum of its proper divisors (733097664).

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

261769536 is a wasteful number, since it uses less digits than its factorization.

261769536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 115 counting only the distinct ones).

The product of its digits is 408240, while the sum is 45.

The square root of 261769536 is about 16179.2934332745. The cubic root of 261769536 is about 639.6951151979.

The spelling of 261769536 in words is "two hundred sixty-one million, seven hundred sixty-nine thousand, five hundred thirty-six".