1591490901 has 64 divisors (see below), whose sum is σ = 2999162880. Its totient is φ = 722960640.

The previous prime is 1591490899. The next prime is 1591490909. The reversal of 1591490901 is 1090941951.

It is not a de Polignac number, because 1591490901 - 2¹ = 1591490899 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 1591490901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1591490909) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43111 + ... + 71003.

It is an arithmetic number, because the mean of its divisors is an integer number (46861920).

Almost surely, 2^1591490901 is an apocalyptic number.

1591490901 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1591490901 is a deficient number, since it is larger than the sum of its proper divisors (1407671979).

1591490901 is a wasteful number, since it uses less digits than its factorization.

1591490901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27946.

The product of its (nonzero) digits is 14580, while the sum is 39.

The square root of 1591490901 is about 39893.4944696501. The cubic root of 1591490901 is about 1167.5300124494.

The spelling of 1591490901 in words is "one billion, five hundred ninety-one million, four hundred ninety thousand, nine hundred one".