1618989 has 4 divisors (see below), whose sum is σ = 2158656. Its totient is φ = 1079324.

The previous prime is 1618979. The next prime is 1619021. The reversal of 1618989 is 9898161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1618989 - 2⁴ = 1618973 is a prime.

It is a super-2 number, since 2×1618989² = 5242250764242, which contains 22 as substring.

It is a D-number.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 1618989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1618909) 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, 269829 + ... + 269834.

It is an arithmetic number, because the mean of its divisors is an integer number (539664).

2^1618989 is an apocalyptic number.

It is an amenable number.

1618989 is a deficient number, since it is larger than the sum of its proper divisors (539667).

1618989 is an equidigital number, since it uses as much as digits as its factorization.

1618989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539666.

The product of its digits is 31104, while the sum is 42.

The square root of 1618989 is about 1272.3949858436. The cubic root of 1618989 is about 117.4215924769.

The spelling of 1618989 in words is "one million, six hundred eighteen thousand, nine hundred eighty-nine".