1396537891 has 16 divisors (see below), whose sum is σ = 1652495040. Its totient is φ = 1154764800.

The previous prime is 1396537889. The next prime is 1396537907. The reversal of 1396537891 is 1987356931.

It is a happy number.

It is not a de Polignac number, because 1396537891 - 2¹ = 1396537889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1396537801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 322855 + ... + 327151.

It is an arithmetic number, because the mean of its divisors is an integer number (103280940).

Almost surely, 2^1396537891 is an apocalyptic number.

1396537891 is a deficient number, since it is larger than the sum of its proper divisors (255957149).

1396537891 is a wasteful number, since it uses less digits than its factorization.

1396537891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5934.

The product of its digits is 1224720, while the sum is 52.

The square root of 1396537891 is about 37370.2808525705. The cubic root of 1396537891 is about 1117.7660325514.

The spelling of 1396537891 in words is "one billion, three hundred ninety-six million, five hundred thirty-seven thousand, eight hundred ninety-one".