621820290 has 144 divisors (see below), whose sum is σ = 1880584128. Its totient is φ = 131144832.

The previous prime is 621820267. The next prime is 621820333. The reversal of 621820290 is 92028126.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 247179 + ... + 249681.

It is an arithmetic number, because the mean of its divisors is an integer number (13059612).

Almost surely, 2^621820290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 621820290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940292064).

621820290 is an abundant number, since it is smaller than the sum of its proper divisors (1258763838).

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

621820290 is a wasteful number, since it uses less digits than its factorization.

621820290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2553 (or 2533 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 621820290 is about 24936.3247091467. The cubic root of 621820290 is about 853.5355801478.

The spelling of 621820290 in words is "six hundred twenty-one million, eight hundred twenty thousand, two hundred ninety".