381572261 has 6 divisors (see below), whose sum is σ = 443869830. Its totient is φ = 327061896.

The previous prime is 381572251. The next prime is 381572297. The reversal of 381572261 is 162275183.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 372721636 + 8850625 = 19306^2 + 2975^2 .

It is not a de Polignac number, because 381572261 - 2¹⁰ = 381571237 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381572201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3893546 + ... + 3893643.

It is an arithmetic number, because the mean of its divisors is an integer number (73978305).

Almost surely, 2^381572261 is an apocalyptic number.

It is an amenable number.

381572261 is a deficient number, since it is larger than the sum of its proper divisors (62297569).

381572261 is an equidigital number, since it uses as much as digits as its factorization.

381572261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7787203 (or 7787196 counting only the distinct ones).

The product of its digits is 20160, while the sum is 35.

The square root of 381572261 is about 19533.8747052396. The cubic root of 381572261 is about 725.3132287436.

The spelling of 381572261 in words is "three hundred eighty-one million, five hundred seventy-two thousand, two hundred sixty-one".