368217721 has 9 divisors (see below), whose sum is σ = 381094533. Its totient is φ = 355764060.

The previous prime is 368217713. The next prime is 368217737. The reversal of 368217721 is 127712863.

The square root of 368217721 is 19189.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 368217721 - 2³ = 368217713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (368217791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 594550 + ... + 595168.

It is an arithmetic number, because the mean of its divisors is an integer number (42343837).

Almost surely, 2^368217721 is an apocalyptic number.

368217721 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

368217721 is the 19189-th square number.

368217721 is the 9595-th centered octagonal number.

It is an amenable number.

368217721 is a deficient number, since it is larger than the sum of its proper divisors (12876812).

368217721 is an frugal number, since it uses more digits than its factorization.

368217721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1300 (or 650 counting only the distinct ones).

The product of its digits is 28224, while the sum is 37.

The cubic root of 368217721 is about 716.7508696689.

Multiplying 368217721 by its product of digits (28224), we get a square (10392576957504 = 3223752²).

It can be divided in two parts, 368 and 217721, that added together give a square (218089 = 467²).

The spelling of 368217721 in words is "three hundred sixty-eight million, two hundred seventeen thousand, seven hundred twenty-one".