961721424 has 50 divisors (see below), whose sum is σ = 2783504570. Its totient is φ = 320573376.

The previous prime is 961721407. The next prime is 961721443. The reversal of 961721424 is 424127169.

It is a happy number.

961721424 is a `hidden beast` number, since 9 + 617 + 2 + 14 + 24 = 666.

It can be written as a sum of positive squares in only one way, i.e., 569681424 + 392040000 = 23868^2 + 19800^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 9 ways as a sum of consecutive naturals, for example, 369739 + ... + 372330.

Almost surely, 2^961721424 is an apocalyptic number.

It is an amenable number.

961721424 is an abundant number, since it is smaller than the sum of its proper divisors (1821783146).

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

961721424 is a wasteful number, since it uses less digits than its factorization.

961721424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742089 (or 742074 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 961721424 is about 31011.6336880210. The cubic root of 961721424 is about 987.0741160703.

The spelling of 961721424 in words is "nine hundred sixty-one million, seven hundred twenty-one thousand, four hundred twenty-four".