396086991 has 4 divisors (see below), whose sum is σ = 528115992. Its totient is φ = 264057992.

The previous prime is 396086989. The next prime is 396086993. The reversal of 396086991 is 199680693.

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

It is an interprime number because it is at equal distance from previous prime (396086989) and next prime (396086993).

It is a cyclic number.

It is not a de Polignac number, because 396086991 - 2¹ = 396086989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (396086993) 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, 66014496 + ... + 66014501.

It is an arithmetic number, because the mean of its divisors is an integer number (132028998).

Almost surely, 2^396086991 is an apocalyptic number.

396086991 is a deficient number, since it is larger than the sum of its proper divisors (132029001).

396086991 is a wasteful number, since it uses less digits than its factorization.

396086991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132029000.

The product of its (nonzero) digits is 629856, while the sum is 51.

The square root of 396086991 is about 19901.9343532231. The cubic root of 396086991 is about 734.3958142789.

It can be divided in two parts, 3960 and 86991, that added together give a triangular number (90951 = T₄₂₆).

The spelling of 396086991 in words is "three hundred ninety-six million, eighty-six thousand, nine hundred ninety-one".