20951347 has 2 divisors, whose sum is σ = 20951348. Its totient is φ = 20951346.

The previous prime is 20951323. The next prime is 20951351. The reversal of 20951347 is 74315902.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20951347 is a prime.

It is a super-2 number, since 2×20951347² = 877917882228818, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20951387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10475673 + 10475674.

It is an arithmetic number, because the mean of its divisors is an integer number (10475674).

Almost surely, 2^20951347 is an apocalyptic number.

20951347 is a deficient number, since it is larger than the sum of its proper divisors (1).

20951347 is an equidigital number, since it uses as much as digits as its factorization.

20951347 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 20951347 is about 4577.2641391993. The cubic root of 20951347 is about 275.6791894900.

The spelling of 20951347 in words is "twenty million, nine hundred fifty-one thousand, three hundred forty-seven".