1491639 has 16 divisors (see below), whose sum is σ = 2073600. Its totient is φ = 953120.

The previous prime is 1491629. The next prime is 1491641. The reversal of 1491639 is 9361941.

It is a cyclic number.

It is not a de Polignac number, because 1491639 - 2¹² = 1487543 is a prime.

1491639 is a modest number, since divided by 1639 gives 149 as remainder.

1491639 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1491629) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9937 + ... + 10085.

It is an arithmetic number, because the mean of its divisors is an integer number (129600).

2^1491639 is an apocalyptic number.

1491639 is a deficient number, since it is larger than the sum of its proper divisors (581961).

1491639 is a wasteful number, since it uses less digits than its factorization.

1491639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270.

The product of its digits is 5832, while the sum is 33.

The square root of 1491639 is about 1221.3267376096. The cubic root of 1491639 is about 114.2583399466.

The spelling of 1491639 in words is "one million, four hundred ninety-one thousand, six hundred thirty-nine".