1551243215461 has 2 divisors, whose sum is σ = 1551243215462. Its totient is φ = 1551243215460.

The previous prime is 1551243215447. The next prime is 1551243215479. The reversal of 1551243215461 is 1645123421551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1432404442561 + 118838772900 = 1196831^2 + 344730^2 .

It is a cyclic number.

It is not a de Polignac number, because 1551243215461 - 2⁵ = 1551243215429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1551243215491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775621607730 + 775621607731.

It is an arithmetic number, because the mean of its divisors is an integer number (775621607731).

Almost surely, 2^{1551243215461} is an apocalyptic number.

It is an amenable number.

1551243215461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1551243215461 is an equidigital number, since it uses as much as digits as its factorization.

1551243215461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144000, while the sum is 40.

The spelling of 1551243215461 in words is "one trillion, five hundred fifty-one billion, two hundred forty-three million, two hundred fifteen thousand, four hundred sixty-one".