617988420 has 384 divisors, whose sum is σ = 2380492800. Its totient is φ = 129890304.

The previous prime is 617988401. The next prime is 617988421. The reversal of 617988420 is 24889716.

617988420 is a `hidden beast` number, since 617 + 9 + 8 + 8 + 4 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (617988421) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3791259 + ... + 3791421.

It is an arithmetic number, because the mean of its divisors is an integer number (6199200).

Almost surely, 2^617988420 is an apocalyptic number.

617988420 is a gapful number since it is divisible by the number (60) 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 617988420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1190246400).

617988420 is an abundant number, since it is smaller than the sum of its proper divisors (1762504380).

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

617988420 is a wasteful number, since it uses less digits than its factorization.

617988420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264 (or 256 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 617988420 is about 24859.3728802639. The cubic root of 617988420 is about 851.7787066617.

The spelling of 617988420 in words is "six hundred seventeen million, nine hundred eighty-eight thousand, four hundred twenty".