1385521391 has 8 divisors (see below), whose sum is σ = 1390072320. Its totient is φ = 1380978328.

The previous prime is 1385521343. The next prime is 1385521399. The reversal of 1385521391 is 1931255831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1385521391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1385521399) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 682520 + ... + 684546.

It is an arithmetic number, because the mean of its divisors is an integer number (173759040).

Almost surely, 2^1385521391 is an apocalyptic number.

1385521391 is a deficient number, since it is larger than the sum of its proper divisors (4550929).

1385521391 is a wasteful number, since it uses less digits than its factorization.

1385521391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3933.

The product of its digits is 32400, while the sum is 38.

The square root of 1385521391 is about 37222.5924809114. The cubic root of 1385521391 is about 1114.8191280944.

The spelling of 1385521391 in words is "one billion, three hundred eighty-five million, five hundred twenty-one thousand, three hundred ninety-one".