191164428 has 192 divisors, whose sum is σ = 623185920. Its totient is φ = 49330944.

The previous prime is 191164411. The next prime is 191164429. The reversal of 191164428 is 824461191.

191164428 is a `hidden beast` number, since 1 + 9 + 1 + 1 + 644 + 2 + 8 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 191164392 and 191164401.

It is not an unprimeable number, because it can be changed into a prime (191164429) 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, 520701 + ... + 521067.

It is an arithmetic number, because the mean of its divisors is an integer number (3245760).

Almost surely, 2^191164428 is an apocalyptic number.

191164428 is a gapful number since it is divisible by the number (18) 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 191164428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311592960).

191164428 is an abundant number, since it is smaller than the sum of its proper divisors (432021492).

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

191164428 is a wasteful number, since it uses less digits than its factorization.

191164428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453 (or 445 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 191164428 is about 13826.2224775967. Note that the first 3 decimals coincide. The cubic root of 191164428 is about 576.0617338347.

The spelling of 191164428 in words is "one hundred ninety-one million, one hundred sixty-four thousand, four hundred twenty-eight".