396487691 has 4 divisors (see below), whose sum is σ = 396539352. Its totient is φ = 396436032.

The previous prime is 396487667. The next prime is 396487699. The reversal of 396487691 is 196784693.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 396487691 - 2¹⁸ = 396225547 is a prime.

It is a super-2 number, since 2×396487691² = 314404978229022962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (396487699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11765 + ... + 30518.

It is an arithmetic number, because the mean of its divisors is an integer number (99134838).

Almost surely, 2^396487691 is an apocalyptic number.

396487691 is a deficient number, since it is larger than the sum of its proper divisors (51661).

396487691 is an equidigital number, since it uses as much as digits as its factorization.

396487691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51660.

The product of its digits is 1959552, while the sum is 53.

The square root of 396487691 is about 19911.9986691442. The cubic root of 396487691 is about 734.6433804550.

Adding to 396487691 its sum of digits (53), we get a square (396487744 = 19912²).

The spelling of 396487691 in words is "three hundred ninety-six million, four hundred eighty-seven thousand, six hundred ninety-one".