11990381 has 6 divisors (see below), whose sum is σ = 12983850. Its totient is φ = 11067888.

The previous prime is 11990371. The next prime is 11990401. The reversal of 11990381 is 18309911.

It can be written as a sum of positive squares in 3 ways, for example, as 198025 + 11792356 = 445^2 + 3434^2 .

It is not a de Polignac number, because 11990381 - 2¹⁰ = 11989357 is a prime.

It is a super-2 number, since 2×11990381² = 287538473050322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11990371) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35306 + ... + 35643.

It is an arithmetic number, because the mean of its divisors is an integer number (2163975).

Almost surely, 2^11990381 is an apocalyptic number.

It is an amenable number.

11990381 is a deficient number, since it is larger than the sum of its proper divisors (993469).

11990381 is an equidigital number, since it uses as much as digits as its factorization.

11990381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70975 (or 70962 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 32.

The square root of 11990381 is about 3462.7129537402. The cubic root of 11990381 is about 228.8816599013.

The spelling of 11990381 in words is "eleven million, nine hundred ninety thousand, three hundred eighty-one".