551621951 has 2 divisors, whose sum is σ = 551621952. Its totient is φ = 551621950.

The previous prime is 551621909. The next prime is 551621971. The reversal of 551621951 is 159126155.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-551621951 is a prime.

It is a Chen prime.

It is equal to p_28926071 and since 551621951 and 28926071 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (551621971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275810975 + 275810976.

It is an arithmetic number, because the mean of its divisors is an integer number (275810976).

Almost surely, 2^551621951 is an apocalyptic number.

551621951 is a deficient number, since it is larger than the sum of its proper divisors (1).

551621951 is an equidigital number, since it uses as much as digits as its factorization.

551621951 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13500, while the sum is 35.

The square root of 551621951 is about 23486.6334539457. The cubic root of 551621951 is about 820.1258734986.

The spelling of 551621951 in words is "five hundred fifty-one million, six hundred twenty-one thousand, nine hundred fifty-one".