191955420 has 144 divisors (see below), whose sum is σ = 610541568. Its totient is φ = 50621760.

The previous prime is 191955409. The next prime is 191955427. The reversal of 191955420 is 24559191.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191955427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 617065 + ... + 617375.

It is an arithmetic number, because the mean of its divisors is an integer number (4239872).

Almost surely, 2^191955420 is an apocalyptic number.

191955420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191955420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (305270784).

191955420 is an abundant number, since it is smaller than the sum of its proper divisors (418586148).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191955420 is a wasteful number, since it uses less digits than its factorization.

191955420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 16200, while the sum is 36.

The square root of 191955420 is about 13854.7977249760. The cubic root of 191955420 is about 576.8551750239.

The spelling of 191955420 in words is "one hundred ninety-one million, nine hundred fifty-five thousand, four hundred twenty".