1955445591 has 16 divisors (see below), whose sum is σ = 2993984640. Its totient is φ = 1122743520.

The previous prime is 1955445589. The next prime is 1955445593.

1955445591 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (1955445589) and next prime (1955445593).

It is not a de Polignac number, because 1955445591 - 2¹ = 1955445589 is a prime.

It is a super-2 number, since 2×1955445591² = 7647534918722678562, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1955445591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1955445593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1558740 + ... + 1559993.

It is an arithmetic number, because the mean of its divisors is an integer number (187124040).

Almost surely, 2^1955445591 is an apocalyptic number.

1955445591 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1955445591 is a deficient number, since it is larger than the sum of its proper divisors (1038539049).

1955445591 is a wasteful number, since it uses less digits than its factorization.

1955445591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3118766.

The product of its digits is 810000, while the sum is 48.

The square root of 1955445591 is about 44220.4205203885. The cubic root of 1955445591 is about 1250.4948634756.

The spelling of 1955445591 in words is "one billion, nine hundred fifty-five million, four hundred forty-five thousand, five hundred ninety-one".