261219387 has 16 divisors (see below), whose sum is σ = 409183488. Its totient is φ = 146136480.

The previous prime is 261219383. The next prime is 261219389. The reversal of 261219387 is 783912162.

It is not a de Polignac number, because 261219387 - 2² = 261219383 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (261219383) 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, 304023 + ... + 304880.

It is an arithmetic number, because the mean of its divisors is an integer number (25573968).

Almost surely, 2^261219387 is an apocalyptic number.

261219387 is a deficient number, since it is larger than the sum of its proper divisors (147964101).

261219387 is a wasteful number, since it uses less digits than its factorization.

261219387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 608930.

The product of its digits is 36288, while the sum is 39.

The square root of 261219387 is about 16162.2828523696. The cubic root of 261219387 is about 639.2466616142.

The spelling of 261219387 in words is "two hundred sixty-one million, two hundred nineteen thousand, three hundred eighty-seven".