1620943 has 4 divisors (see below), whose sum is σ = 1636200. Its totient is φ = 1605688.

The previous prime is 1620929. The next prime is 1620961. The reversal of 1620943 is 3490261.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3490261 = 199 ⋅17539.

It is a cyclic number.

It is not a de Polignac number, because 1620943 - 2⁹ = 1620431 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620923) 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, 7468 + ... + 7681.

It is an arithmetic number, because the mean of its divisors is an integer number (409050).

2^1620943 is an apocalyptic number.

1620943 is a deficient number, since it is larger than the sum of its proper divisors (15257).

1620943 is a wasteful number, since it uses less digits than its factorization.

1620943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15256.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 1620943 is about 1273.1625976284. The cubic root of 1620943 is about 117.4688132110.

It can be divided in two parts, 1 and 620943, that added together give a square (620944 = 788²).

The spelling of 1620943 in words is "one million, six hundred twenty thousand, nine hundred forty-three".