261620436 has 48 divisors (see below), whose sum is σ = 761080320. Its totient is φ = 67953120.

The previous prime is 261620413. The next prime is 261620441. The reversal of 261620436 is 634026162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 140646 + ... + 142493.

It is an arithmetic number, because the mean of its divisors is an integer number (15855840).

Almost surely, 2^261620436 is an apocalyptic number.

It is an amenable number.

261620436 is an abundant number, since it is smaller than the sum of its proper divisors (499459884).

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

261620436 is a wasteful number, since it uses less digits than its factorization.

261620436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283164 (or 283162 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 261620436 is about 16174.6850355733. The cubic root of 261620436 is about 639.5736385515.

Adding to 261620436 its reverse (634026162), we get a palindrome (895646598).

The spelling of 261620436 in words is "two hundred sixty-one million, six hundred twenty thousand, four hundred thirty-six".