1661254539 has 8 divisors (see below), whose sum is σ = 2531435520. Its totient is φ = 949288296.

The previous prime is 1661254537. The next prime is 1661254547. The reversal of 1661254539 is 9354521661.

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

It is not a de Polignac number, because 1661254539 - 2¹ = 1661254537 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1661254539.

It is not an unprimeable number, because it can be changed into a prime (1661254537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39553659 + ... + 39553700.

It is an arithmetic number, because the mean of its divisors is an integer number (316429440).

Almost surely, 2^1661254539 is an apocalyptic number.

1661254539 is a deficient number, since it is larger than the sum of its proper divisors (870180981).

1661254539 is an equidigital number, since it uses as much as digits as its factorization.

1661254539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79107369.

The product of its digits is 194400, while the sum is 42.

The square root of 1661254539 is about 40758.4903915736. The cubic root of 1661254539 is about 1184.3463524690.

The spelling of 1661254539 in words is "one billion, six hundred sixty-one million, two hundred fifty-four thousand, five hundred thirty-nine".