1618021 has 4 divisors (see below), whose sum is σ = 1703200. Its totient is φ = 1532844.

The previous prime is 1618007. The next prime is 1618033. The reversal of 1618021 is 1208161.

1618021 = 58² + 59² + ... + 171².

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, and also an emirpimes, since its reverse is a distinct semiprime: 1208161 = 37 ⋅32653.

It is not a de Polignac number, because 1618021 - 2⁵ = 1617989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 85159 = 1618021 / (1 + 6 + 1 + 8 + 0 + 2 + 1).

It is a Duffinian number.

1618021 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1618021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1618051) 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, 42561 + ... + 42598.

It is an arithmetic number, because the mean of its divisors is an integer number (425800).

2^1618021 is an apocalyptic number.

It is an amenable number.

1618021 is a deficient number, since it is larger than the sum of its proper divisors (85179).

1618021 is an equidigital number, since it uses as much as digits as its factorization.

1618021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85178.

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 1618021 is about 1272.0145439420. The cubic root of 1618021 is about 117.3981855313.

The spelling of 1618021 in words is "one million, six hundred eighteen thousand, twenty-one".