1620461999 has 4 divisors (see below), whose sum is σ = 1745112936. Its totient is φ = 1495811064.

The previous prime is 1620461959. The next prime is 1620462031. The reversal of 1620461999 is 9991640261.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1620461999 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 (1620461929) 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, 62325449 + ... + 62325474.

It is an arithmetic number, because the mean of its divisors is an integer number (436278234).

Almost surely, 2^1620461999 is an apocalyptic number.

1620461999 is a deficient number, since it is larger than the sum of its proper divisors (124650937).

1620461999 is a wasteful number, since it uses less digits than its factorization.

1620461999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124650936.

The product of its (nonzero) digits is 209952, while the sum is 47.

The square root of 1620461999 is about 40254.9624145893. The cubic root of 1620461999 is about 1174.5719277228.

The spelling of 1620461999 in words is "one billion, six hundred twenty million, four hundred sixty-one thousand, nine hundred ninety-nine".