1620975 has 12 divisors (see below), whose sum is σ = 2680136. Its totient is φ = 864480.

The previous prime is 1620973. The next prime is 1620977. The reversal of 1620975 is 5790261.

It is an interprime number because it is at equal distance from previous prime (1620973) and next prime (1620977).

It is not a de Polignac number, because 1620975 - 2¹ = 1620973 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 (1620973) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10732 + ... + 10881.

2^1620975 is an apocalyptic number.

1620975 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1620975 is a deficient number, since it is larger than the sum of its proper divisors (1059161).

1620975 is a wasteful number, since it uses less digits than its factorization.

1620975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21626 (or 21621 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 30.

The square root of 1620975 is about 1273.1751646965. The cubic root of 1620975 is about 117.4695862132.

The spelling of 1620975 in words is "one million, six hundred twenty thousand, nine hundred seventy-five".