261563424 has 48 divisors (see below), whose sum is σ = 722746080. Its totient is φ = 82598400.

The previous prime is 261563387. The next prime is 261563447. The reversal of 261563424 is 424365162.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69877 + ... + 73524.

It is an arithmetic number, because the mean of its divisors is an integer number (15057210).

Almost surely, 2^261563424 is an apocalyptic number.

261563424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

261563424 is an abundant number, since it is smaller than the sum of its proper divisors (461182656).

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

261563424 is a wasteful number, since it uses less digits than its factorization.

261563424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143433 (or 143425 counting only the distinct ones).

The product of its digits is 34560, while the sum is 33.

The square root of 261563424 is about 16172.9225559266. The cubic root of 261563424 is about 639.5271768124.

The spelling of 261563424 in words is "two hundred sixty-one million, five hundred sixty-three thousand, four hundred twenty-four".