1661454723 has 16 divisors (see below), whose sum is σ = 2235212672. Its totient is φ = 1097712000.

The previous prime is 1661454719. The next prime is 1661454733. The reversal of 1661454723 is 3274541661.

It is a happy number.

It is not a de Polignac number, because 1661454723 - 2² = 1661454719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1661454733) 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, 147108 + ... + 157998.

It is an arithmetic number, because the mean of its divisors is an integer number (139700792).

Almost surely, 2^1661454723 is an apocalyptic number.

1661454723 is a deficient number, since it is larger than the sum of its proper divisors (573757949).

1661454723 is a wasteful number, since it uses less digits than its factorization.

1661454723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11346.

The product of its digits is 120960, while the sum is 39.

The square root of 1661454723 is about 40760.9460513369. The cubic root of 1661454723 is about 1184.3939224755.

The spelling of 1661454723 in words is "one billion, six hundred sixty-one million, four hundred fifty-four thousand, seven hundred twenty-three".