1620511920 has 400 divisors, whose sum is σ = 5989116672. Its totient is φ = 405250560.

The previous prime is 1620511891. The next prime is 1620511951. The reversal of 1620511920 is 291150261.

1620511920 is a `hidden beast` number, since 1 + 62 + 0 + 511 + 92 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 12370255 + ... + 12370385.

Almost surely, 2^1620511920 is an apocalyptic number.

1620511920 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 1620511920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2994558336).

1620511920 is an abundant number, since it is smaller than the sum of its proper divisors (4368604752).

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

1620511920 is a wasteful number, since it uses less digits than its factorization.

1620511920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262 (or 247 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 1620511920 is about 40255.5824700128. The cubic root of 1620511920 is about 1174.5839891396.

The spelling of 1620511920 in words is "one billion, six hundred twenty million, five hundred eleven thousand, nine hundred twenty".