391761216 has 336 divisors, whose sum is σ = 1430901888. Its totient is φ = 100362240.

The previous prime is 391761211. The next prime is 391761257. The reversal of 391761216 is 612167193.

391761216 is a `hidden beast` number, since 39 + 1 + 7 + 612 + 1 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391761211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5366556 + ... + 5366628.

Almost surely, 2^391761216 is an apocalyptic number.

391761216 is a gapful number since it is divisible by the number (36) 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 391761216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (715450944).

391761216 is an abundant number, since it is smaller than the sum of its proper divisors (1039140672).

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

391761216 is a wasteful number, since it uses less digits than its factorization.

391761216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 96 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 391761216 is about 19792.9587479992. The cubic root of 391761216 is about 731.7125091586.

The spelling of 391761216 in words is "three hundred ninety-one million, seven hundred sixty-one thousand, two hundred sixteen".