1618421 has 6 divisors (see below), whose sum is σ = 1882710. Its totient is φ = 1387176.

The previous prime is 1618411. The next prime is 1618433. The reversal of 1618421 is 1248161.

It can be written as a sum of positive squares in only one way, i.e., 828100 + 790321 = 910^2 + 889^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1618421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1618411) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16466 + ... + 16563.

It is an arithmetic number, because the mean of its divisors is an integer number (313785).

2^1618421 is an apocalyptic number.

It is an amenable number.

1618421 is a deficient number, since it is larger than the sum of its proper divisors (264289).

1618421 is an equidigital number, since it uses as much as digits as its factorization.

1618421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33043 (or 33036 counting only the distinct ones).

The product of its digits is 384, while the sum is 23.

The square root of 1618421 is about 1272.1717651324. The cubic root of 1618421 is about 117.4078589544.

The spelling of 1618421 in words is "one million, six hundred eighteen thousand, four hundred twenty-one".