321690072 has 128 divisors (see below), whose sum is σ = 907925760. Its totient is φ = 94149120.

The previous prime is 321690071. The next prime is 321690073. The reversal of 321690072 is 270096123.

It is an interprime number because it is at equal distance from previous prime (321690071) and next prime (321690073).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321690071) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1161198 + ... + 1161474.

It is an arithmetic number, because the mean of its divisors is an integer number (7093170).

Almost surely, 2^321690072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321690072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (453962880).

321690072 is an abundant number, since it is smaller than the sum of its proper divisors (586235688).

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

321690072 is a wasteful number, since it uses less digits than its factorization.

321690072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 433 (or 429 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 321690072 is about 17935.7205598214. The cubic root of 321690072 is about 685.1924243182.

The spelling of 321690072 in words is "three hundred twenty-one million, six hundred ninety thousand, seventy-two".