1620540012 has 96 divisors (see below), whose sum is σ = 4664084992. Its totient is φ = 426456576.

The previous prime is 1620540007. The next prime is 1620540029. The reversal of 1620540012 is 2100450261.

It is a super-2 number, since 2×1620540012² = 5252299860985920288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 595968 + ... + 598680.

Almost surely, 2^1620540012 is an apocalyptic number.

1620540012 is a gapful number since it is divisible by the number (12) 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 1620540012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2332042496).

1620540012 is an abundant number, since it is smaller than the sum of its proper divisors (3043544980).

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

1620540012 is a wasteful number, since it uses less digits than its factorization.

1620540012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3287 (or 3285 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 1620540012 is about 40255.9313890512. The cubic root of 1620540012 is about 1174.5907763411.

Adding to 1620540012 its reverse (2100450261), we get a palindrome (3720990273).

The spelling of 1620540012 in words is "one billion, six hundred twenty million, five hundred forty thousand, twelve".