261941904 has 320 divisors, whose sum is σ = 933273600. Its totient is φ = 68677632.

The previous prime is 261941903. The next prime is 261941929. The reversal of 261941904 is 409149162.

It is a happy number.

It is a super-2 number, since 2×261941904² = 137227122142290432, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (261941903) 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, 2700384 + ... + 2700480.

It is an arithmetic number, because the mean of its divisors is an integer number (2916480).

Almost surely, 2^261941904 is an apocalyptic number.

261941904 is a gapful number since it is divisible by the number (24) 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 261941904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (466636800).

261941904 is an abundant number, since it is smaller than the sum of its proper divisors (671331696).

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

261941904 is a wasteful number, since it uses less digits than its factorization.

261941904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187 (or 175 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 261941904 is about 16184.6193653110. The cubic root of 261941904 is about 639.8354915718.

It can be divided in two parts, 2619 and 41904, that multiplied together give a square (109746576 = 10476²).

The spelling of 261941904 in words is "two hundred sixty-one million, nine hundred forty-one thousand, nine hundred four".