321690420 has 192 divisors, whose sum is σ = 1064448000. Its totient is φ = 80479872.

The previous prime is 321690407. The next prime is 321690433. The reversal of 321690420 is 24096123.

It is an interprime number because it is at equal distance from previous prime (321690407) and next prime (321690433).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 732561 + ... + 732999.

It is an arithmetic number, because the mean of its divisors is an integer number (5544000).

Almost surely, 2^321690420 is an apocalyptic number.

321690420 is a gapful number since it is divisible by the number (30) 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 321690420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (532224000).

321690420 is an abundant number, since it is smaller than the sum of its proper divisors (742757580).

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

321690420 is a wasteful number, since it uses less digits than its factorization.

321690420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539 (or 531 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 321690420 is about 17935.7302611296. The cubic root of 321690420 is about 685.1926713954.

It can be divided in two parts, 3216 and 90420, that added together give a square (93636 = 306²).

The spelling of 321690420 in words is "three hundred twenty-one million, six hundred ninety thousand, four hundred twenty".