206051152421 has 2 divisors, whose sum is σ = 206051152422. Its totient is φ = 206051152420.

The previous prime is 206051152409. The next prime is 206051152423. The reversal of 206051152421 is 124251150602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 201969348100 + 4081804321 = 449410^2 + 63889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206051152421 is a prime.

It is a super-2 number, since 2×206051152421² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 206051152423, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206051152423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103025576210 + 103025576211.

It is an arithmetic number, because the mean of its divisors is an integer number (103025576211).

Almost surely, 2^206051152421 is an apocalyptic number.

It is an amenable number.

206051152421 is a deficient number, since it is larger than the sum of its proper divisors (1).

206051152421 is an equidigital number, since it uses as much as digits as its factorization.

206051152421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 29.

The spelling of 206051152421 in words is "two hundred six billion, fifty-one million, one hundred fifty-two thousand, four hundred twenty-one".