396129409 has 9 divisors (see below), whose sum is σ = 429225219. Its totient is φ = 365419080.

The previous prime is 396129407. The next prime is 396129431. The reversal of 396129409 is 904921693.

The square root of 396129409 is 19903.

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

It can be written as a sum of positive squares in only one way, i.e., 58599025 + 337530384 = 7655^2 + 18372^2 .

It is not a de Polignac number, because 396129409 - 2¹ = 396129407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (396129401) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 257974 + ... + 259504.

It is an arithmetic number, because the mean of its divisors is an integer number (47691691).

Almost surely, 2^396129409 is an apocalyptic number.

396129409 is the 19903-rd square number.

396129409 is the 9952-nd centered octagonal number.

It is an amenable number.

396129409 is a deficient number, since it is larger than the sum of its proper divisors (33095810).

396129409 is an frugal number, since it uses more digits than its factorization.

396129409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3088 (or 1544 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 43.

The cubic root of 396129409 is about 734.4220294710.

Multiplying 396129409 by its product of nonzero digits (104976), we get a square (41584080839184 = 6448572²).

The spelling of 396129409 in words is "three hundred ninety-six million, one hundred twenty-nine thousand, four hundred nine".