190380781 has 2 divisors, whose sum is σ = 190380782. Its totient is φ = 190380780.

The previous prime is 190380767. The next prime is 190380793. The reversal of 190380781 is 187083091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 176624100 + 13756681 = 13290^2 + 3709^2 .

It is a cyclic number.

It is not a de Polignac number, because 190380781 - 2²¹ = 188283629 is a prime.

It is a super-2 number, since 2×190380781² = 72489683548339922, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 190380781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (190380721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95190390 + 95190391.

It is an arithmetic number, because the mean of its divisors is an integer number (95190391).

Almost surely, 2^190380781 is an apocalyptic number.

It is an amenable number.

190380781 is a deficient number, since it is larger than the sum of its proper divisors (1).

190380781 is an equidigital number, since it uses as much as digits as its factorization.

190380781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 190380781 is about 13797.8542172325. The cubic root of 190380781 is about 575.2734991269.

The spelling of 190380781 in words is "one hundred ninety million, three hundred eighty thousand, seven hundred eighty-one".