10981921 has 2 divisors, whose sum is σ = 10981922. Its totient is φ = 10981920.

The previous prime is 10981913. The next prime is 10981931. The reversal of 10981921 is 12918901.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9541921 + 1440000 = 3089^2 + 1200^2 .

It is an emirp because it is prime and its reverse (12918901) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10981921 - 2³ = 10981913 is a prime.

It is not a weakly prime, because it can be changed into another prime (10981931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5490960 + 5490961.

It is an arithmetic number, because the mean of its divisors is an integer number (5490961).

Almost surely, 2^10981921 is an apocalyptic number.

It is an amenable number.

10981921 is a deficient number, since it is larger than the sum of its proper divisors (1).

10981921 is an equidigital number, since it uses as much as digits as its factorization.

10981921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 10981921 is about 3313.8981577592. The cubic root of 10981921 is about 222.2761018335.

The spelling of 10981921 in words is "ten million, nine hundred eighty-one thousand, nine hundred twenty-one".