20981374 has 4 divisors (see below), whose sum is σ = 31472064. Its totient is φ = 10490686.

The previous prime is 20981371. The next prime is 20981399. The reversal of 20981374 is 47318902.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20981371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5245342 + ... + 5245345.

It is an arithmetic number, because the mean of its divisors is an integer number (7868016).

Almost surely, 2^20981374 is an apocalyptic number.

20981374 is a deficient number, since it is larger than the sum of its proper divisors (10490690).

20981374 is a wasteful number, since it uses less digits than its factorization.

20981374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10490689.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 20981374 is about 4580.5429809139. The cubic root of 20981374 is about 275.8108256984.

The spelling of 20981374 in words is "twenty million, nine hundred eighty-one thousand, three hundred seventy-four".