391636049 has 4 divisors (see below), whose sum is σ = 447584064. Its totient is φ = 335688036.

The previous prime is 391636013. The next prime is 391636057. The reversal of 391636049 is 940636193.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 391636049 - 2²⁸ = 123200593 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 391635997 and 391636015.

It is not an unprimeable number, because it can be changed into a prime (391636099) 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, 27973997 + ... + 27974010.

It is an arithmetic number, because the mean of its divisors is an integer number (111896016).

Almost surely, 2^391636049 is an apocalyptic number.

It is an amenable number.

391636049 is a deficient number, since it is larger than the sum of its proper divisors (55948015).

391636049 is an equidigital number, since it uses as much as digits as its factorization.

391636049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55948014.

The product of its (nonzero) digits is 104976, while the sum is 41.

The square root of 391636049 is about 19789.7965881411. The cubic root of 391636049 is about 731.6345739168.

The spelling of 391636049 in words is "three hundred ninety-one million, six hundred thirty-six thousand, forty-nine".