11278921 has 2 divisors, whose sum is σ = 11278922. Its totient is φ = 11278920.

The previous prime is 11278907. The next prime is 11278933. The reversal of 11278921 is 12987211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7096896 + 4182025 = 2664^2 + 2045^2 .

It is a cyclic number.

It is not a de Polignac number, because 11278921 - 2⁵ = 11278889 is a prime.

It is not a weakly prime, because it can be changed into another prime (11278721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5639460 + 5639461.

It is an arithmetic number, because the mean of its divisors is an integer number (5639461).

Almost surely, 2^11278921 is an apocalyptic number.

It is an amenable number.

11278921 is a deficient number, since it is larger than the sum of its proper divisors (1).

11278921 is an equidigital number, since it uses as much as digits as its factorization.

11278921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 31.

The square root of 11278921 is about 3358.4104871204. The cubic root of 11278921 is about 224.2620829614.

The spelling of 11278921 in words is "eleven million, two hundred seventy-eight thousand, nine hundred twenty-one".