136390221 has 12 divisors (see below), whose sum is σ = 214918080. Its totient is φ = 82660680.

The previous prime is 136390187. The next prime is 136390223. The reversal of 136390221 is 122093631.

136390221 is a `hidden beast` number, since 1 + 3 + 639 + 0 + 2 + 21 = 666.

It is not a de Polignac number, because 136390221 - 2¹⁵ = 136357453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136390223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 688741 + ... + 688938.

It is an arithmetic number, because the mean of its divisors is an integer number (17909840).

Almost surely, 2^136390221 is an apocalyptic number.

136390221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

136390221 is a deficient number, since it is larger than the sum of its proper divisors (78527859).

136390221 is a wasteful number, since it uses less digits than its factorization.

136390221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377696 (or 1377693 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 136390221 is about 11678.6223930736. The cubic root of 136390221 is about 514.7476955606.

The spelling of 136390221 in words is "one hundred thirty-six million, three hundred ninety thousand, two hundred twenty-one".