261943401 has 16 divisors (see below), whose sum is σ = 362726144. Its totient is φ = 168016464.

The previous prime is 261943373. The next prime is 261943439. The reversal of 261943401 is 104349162.

It is not a de Polignac number, because 261943401 - 2⁵ = 261943369 is a prime.

It is a super-2 number, since 2×261943401² = 137228690654893602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261943441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6511 + ... + 23796.

It is an arithmetic number, because the mean of its divisors is an integer number (22670384).

Almost surely, 2^261943401 is an apocalyptic number.

It is an amenable number.

261943401 is a deficient number, since it is larger than the sum of its proper divisors (100782743).

261943401 is a wasteful number, since it uses less digits than its factorization.

261943401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30420.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 261943401 is about 16184.6656128571. The cubic root of 261943401 is about 639.8367104577.

The spelling of 261943401 in words is "two hundred sixty-one million, nine hundred forty-three thousand, four hundred one".