191628649 has 9 divisors (see below), whose sum is σ = 194937687. Its totient is φ = 188375544.

The previous prime is 191628631. The next prime is 191628653. The reversal of 191628649 is 946826191.

It is a happy number.

The square root of 191628649 is 13843.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 133564249 + 58064400 = 11557^2 + 7620^2 .

It is not a de Polignac number, because 191628649 - 2¹⁷ = 191497577 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 191628599 and 191628608.

It is not an unprimeable number, because it can be changed into a prime (191628149) 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 8 ways as a sum of consecutive naturals, for example, 1508824 + ... + 1508950.

It is an arithmetic number, because the mean of its divisors is an integer number (21659743).

Almost surely, 2^191628649 is an apocalyptic number.

191628649 is the 13843-rd square number.

191628649 is the 6922-nd centered octagonal number.

It is an amenable number.

191628649 is a deficient number, since it is larger than the sum of its proper divisors (3309038).

191628649 is an frugal number, since it uses more digits than its factorization.

191628649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472 (or 236 counting only the distinct ones).

The product of its digits is 186624, while the sum is 46.

The cubic root of 191628649 is about 576.5276569534.

Multiplying 191628649 by its product of digits (186624), we get a square (35762504990976 = 5980176²).

The spelling of 191628649 in words is "one hundred ninety-one million, six hundred twenty-eight thousand, six hundred forty-nine".