961821291 has 32 divisors (see below), whose sum is σ = 1449930240. Its totient is φ = 563802624.

The previous prime is 961821271. The next prime is 961821299. The reversal of 961821291 is 192128169.

It is not a de Polignac number, because 961821291 - 2¹⁹ = 961297003 is a prime.

It is not an unprimeable number, because it can be changed into a prime (961821299) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 40905 + ... + 59973.

It is an arithmetic number, because the mean of its divisors is an integer number (45310320).

Almost surely, 2^961821291 is an apocalyptic number.

961821291 is a deficient number, since it is larger than the sum of its proper divisors (488108949).

961821291 is a wasteful number, since it uses less digits than its factorization.

961821291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19155.

The product of its digits is 15552, while the sum is 39.

The square root of 961821291 is about 31013.2438000284. The cubic root of 961821291 is about 987.1082814451.

The spelling of 961821291 in words is "nine hundred sixty-one million, eight hundred twenty-one thousand, two hundred ninety-one".