391940534 has 4 divisors (see below), whose sum is σ = 587910804. Its totient is φ = 195970266.

The previous prime is 391940513. The next prime is 391940537. The reversal of 391940534 is 435049193.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391940537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97985132 + ... + 97985135.

It is an arithmetic number, because the mean of its divisors is an integer number (146977701).

Almost surely, 2^391940534 is an apocalyptic number.

391940534 is a deficient number, since it is larger than the sum of its proper divisors (195970270).

391940534 is a wasteful number, since it uses less digits than its factorization.

391940534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195970269.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 391940534 is about 19797.4880729854. The cubic root of 391940534 is about 731.8241326036.

The spelling of 391940534 in words is "three hundred ninety-one million, nine hundred forty thousand, five hundred thirty-four".