16121489 has 4 divisors (see below), whose sum is σ = 16210740. Its totient is φ = 16032240.

The previous prime is 16121471. The next prime is 16121509. The reversal of 16121489 is 98412161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1067089 + 15054400 = 1033^2 + 3880^2 .

It is a cyclic number.

It is not a de Polignac number, because 16121489 - 2¹⁶ = 16055953 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16121429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44354 + ... + 44715.

It is an arithmetic number, because the mean of its divisors is an integer number (4052685).

Almost surely, 2^16121489 is an apocalyptic number.

It is an amenable number.

16121489 is a deficient number, since it is larger than the sum of its proper divisors (89251).

16121489 is an equidigital number, since it uses as much as digits as its factorization.

16121489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89250.

The product of its digits is 3456, while the sum is 32.

The square root of 16121489 is about 4015.1574066280. The cubic root of 16121489 is about 252.6203798116.

The spelling of 16121489 in words is "sixteen million, one hundred twenty-one thousand, four hundred eighty-nine".