1620457920 has 336 divisors, whose sum is σ = 5918179680. Its totient is φ = 417374208.

The previous prime is 1620457907. The next prime is 1620457933. The reversal of 1620457920 is 297540261.

1620457920 is a `hidden beast` number, since 1 + 62 + 0 + 4 + 579 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (1620457907) and next prime (1620457933).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11828092 + ... + 11828228.

It is an arithmetic number, because the mean of its divisors is an integer number (17613630).

Almost surely, 2^1620457920 is an apocalyptic number.

1620457920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1620457920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2959089840).

1620457920 is an abundant number, since it is smaller than the sum of its proper divisors (4297721760).

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

1620457920 is a wasteful number, since it uses less digits than its factorization.

1620457920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 1620457920 is about 40254.9117499964. The cubic root of 1620457920 is about 1174.5709421843.

The spelling of 1620457920 in words is "one billion, six hundred twenty million, four hundred fifty-seven thousand, nine hundred twenty".