261380420 has 24 divisors (see below), whose sum is σ = 627313344. Its totient is φ = 89616096.

The previous prime is 261380417. The next prime is 261380447. The reversal of 261380420 is 24083162.

It is a self number, because there is not a number n which added to its sum of digits gives 261380420.

It is an unprimeable number.

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, 933362 + ... + 933641.

It is an arithmetic number, because the mean of its divisors is an integer number (26138056).

Almost surely, 2^261380420 is an apocalyptic number.

261380420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261380420 is an abundant number, since it is smaller than the sum of its proper divisors (365932924).

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

261380420 is a wasteful number, since it uses less digits than its factorization.

261380420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1867019 (or 1867017 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 261380420 is about 16167.2638377680. The cubic root of 261380420 is about 639.3779926806.

The spelling of 261380420 in words is "two hundred sixty-one million, three hundred eighty thousand, four hundred twenty".