20342981 has 2 divisors, whose sum is σ = 20342982. Its totient is φ = 20342980.

The previous prime is 20342969. The next prime is 20343019. The reversal of 20342981 is 18924302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11282881 + 9060100 = 3359^2 + 3010^2 .

It is a cyclic number.

It is not a de Polignac number, because 20342981 - 2¹⁰ = 20341957 is a prime.

It is a super-2 number, since 2×20342981² = 827673751932722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20342911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10171490 + 10171491.

It is an arithmetic number, because the mean of its divisors is an integer number (10171491).

Almost surely, 2^20342981 is an apocalyptic number.

It is an amenable number.

20342981 is a deficient number, since it is larger than the sum of its proper divisors (1).

20342981 is an equidigital number, since it uses as much as digits as its factorization.

20342981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 20342981 is about 4510.3193900211. The cubic root of 20342981 is about 272.9846315151.

The spelling of 20342981 in words is "twenty million, three hundred forty-two thousand, nine hundred eighty-one".