1620361 has 4 divisors (see below), whose sum is σ = 1659924. Its totient is φ = 1580800.

The previous prime is 1620347. The next prime is 1620371. The reversal of 1620361 is 1630261.

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 32761 + 1587600 = 181^2 + 1260^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620361 - 2⁵ = 1620329 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620331) 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, 19720 + ... + 19801.

It is an arithmetic number, because the mean of its divisors is an integer number (414981).

2^1620361 is an apocalyptic number.

It is an amenable number.

1620361 is a deficient number, since it is larger than the sum of its proper divisors (39563).

1620361 is an equidigital number, since it uses as much as digits as its factorization.

1620361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39562.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 1620361 is about 1272.9340124296. The cubic root of 1620361 is about 117.4547524589.

The spelling of 1620361 in words is "one million, six hundred twenty thousand, three hundred sixty-one".