1551222551 has 2 divisors, whose sum is σ = 1551222552. Its totient is φ = 1551222550.

The previous prime is 1551222527. The next prime is 1551222553. The reversal of 1551222551 is 1552221551.

It is a strong prime.

It is an emirp because it is prime and its reverse (1552221551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1551222551 - 2¹⁰ = 1551221527 is a prime.

Together with 1551222553, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1551222553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775611275 + 775611276.

It is an arithmetic number, because the mean of its divisors is an integer number (775611276).

Almost surely, 2^1551222551 is an apocalyptic number.

1551222551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1551222551 is an equidigital number, since it uses as much as digits as its factorization.

1551222551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5000, while the sum is 29.

The square root of 1551222551 is about 39385.5627229065. The cubic root of 1551222551 is about 1157.5987164586.

The spelling of 1551222551 in words is "one billion, five hundred fifty-one million, two hundred twenty-two thousand, five hundred fifty-one".