1620745806 has 16 divisors (see below), whose sum is σ = 3267016704. Its totient is φ = 535994424.

The previous prime is 1620745769. The next prime is 1620745849. The reversal of 1620745806 is 6085470261.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1062720 + ... + 1064243.

It is an arithmetic number, because the mean of its divisors is an integer number (204188544).

Almost surely, 2^1620745806 is an apocalyptic number.

1620745806 is an abundant number, since it is smaller than the sum of its proper divisors (1646270898).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1620745806 is a wasteful number, since it uses less digits than its factorization.

1620745806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2127095.

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 1620745806 is about 40258.4873784398. The cubic root of 1620745806 is about 1174.6404950565.

The spelling of 1620745806 in words is "one billion, six hundred twenty million, seven hundred forty-five thousand, eight hundred six".