263221540 has 24 divisors (see below), whose sum is σ = 585281592. Its totient is φ = 99095040.

The previous prime is 263221537. The next prime is 263221549. The reversal of 263221540 is 45122362.

It can be written as a sum of positive squares in 4 ways, for example, as 5875776 + 257345764 = 2424^2 + 16042^2 .

It is not an unprimeable number, because it can be changed into a prime (263221549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 386751 + ... + 387430.

It is an arithmetic number, because the mean of its divisors is an integer number (24386733).

Almost surely, 2^263221540 is an apocalyptic number.

263221540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

263221540 is an abundant number, since it is smaller than the sum of its proper divisors (322060052).

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

263221540 is a wasteful number, since it uses less digits than its factorization.

263221540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 774207 (or 774205 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 263221540 is about 16224.1036732388. The cubic root of 263221540 is about 640.8757055313.

The spelling of 263221540 in words is "two hundred sixty-three million, two hundred twenty-one thousand, five hundred forty".