1620356940 has 96 divisors (see below), whose sum is σ = 5087544000. Its totient is φ = 428115456.

The previous prime is 1620356929. The next prime is 1620356953. The reversal of 1620356940 is 496530261.

It is a happy number.

It is a super-2 number, since 2×1620356940² = 5251113226012327200, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 1620356895 and 1620356904.

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, 45096 + ... + 72624.

It is an arithmetic number, because the mean of its divisors is an integer number (52995250).

Almost surely, 2^1620356940 is an apocalyptic number.

1620356940 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 1620356940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2543772000).

1620356940 is an abundant number, since it is smaller than the sum of its proper divisors (3467187060).

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

1620356940 is a wasteful number, since it uses less digits than its factorization.

1620356940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27656 (or 27648 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 1620356940 is about 40253.6574735762. The cubic root of 1620356940 is about 1174.5465436000.

The spelling of 1620356940 in words is "one billion, six hundred twenty million, three hundred fifty-six thousand, nine hundred forty".