1001001386491 has 4 divisors (see below), whose sum is σ = 1001005398432. Its totient is φ = 1000997374552.

The previous prime is 1001001386477. The next prime is 1001001386507. The reversal of 1001001386491 is 1946831001001.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001001386491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001001386471) 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, 1604995 + ... + 2139628.

It is an arithmetic number, because the mean of its divisors is an integer number (250251349608).

Almost surely, 2^{1001001386491} is an apocalyptic number.

1001001386491 is a deficient number, since it is larger than the sum of its proper divisors (4011941).

1001001386491 is an equidigital number, since it uses as much as digits as its factorization.

1001001386491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4011940.

The product of its (nonzero) digits is 5184, while the sum is 34.

Adding to 1001001386491 its reverse (1946831001001), we get a palindrome (2947832387492).

The spelling of 1001001386491 in words is "one trillion, one billion, one million, three hundred eighty-six thousand, four hundred ninety-one".