15780961 has 8 divisors (see below), whose sum is σ = 18264320. Its totient is φ = 13354848.

The previous prime is 15780949. The next prime is 15780983. The reversal of 15780961 is 16908751.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15780961 - 2¹¹ = 15778913 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 15780961.

It is not an unprimeable number, because it can be changed into a prime (15780991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13716 + ... + 14821.

It is an arithmetic number, because the mean of its divisors is an integer number (2283040).

Almost surely, 2^15780961 is an apocalyptic number.

It is an amenable number.

15780961 is a deficient number, since it is larger than the sum of its proper divisors (2483359).

15780961 is an equidigital number, since it uses as much as digits as its factorization.

15780961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28623.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 15780961 is about 3972.5257708415. The cubic root of 15780961 is about 250.8290397335.

It can be divided in two parts, 157 and 80961, that added together give a palindrome (81118).

The spelling of 15780961 in words is "fifteen million, seven hundred eighty thousand, nine hundred sixty-one".