391223536 has 40 divisors (see below), whose sum is σ = 831540528. Its totient is φ = 176832000.

The previous prime is 391223531. The next prime is 391223551. The reversal of 391223536 is 635322193.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391223531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25716 + ... + 37996.

Almost surely, 2^391223536 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 391223536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (415770264).

391223536 is an abundant number, since it is smaller than the sum of its proper divisors (440316992).

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

391223536 is a wasteful number, since it uses less digits than its factorization.

391223536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12481 (or 12475 counting only the distinct ones).

The product of its digits is 29160, while the sum is 34.

The square root of 391223536 is about 19779.3714763640. The cubic root of 391223536 is about 731.3776050622.

The spelling of 391223536 in words is "three hundred ninety-one million, two hundred twenty-three thousand, five hundred thirty-six".