1554556121 has 2 divisors, whose sum is σ = 1554556122. Its totient is φ = 1554556120.

The previous prime is 1554556103. The next prime is 1554556127. The reversal of 1554556121 is 1216554551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1434894400 + 119661721 = 37880^2 + 10939^2 .

It is an emirp because it is prime and its reverse (1216554551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1554556121 - 2¹⁰ = 1554555097 is a prime.

It is not a weakly prime, because it can be changed into another prime (1554556127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 777278060 + 777278061.

It is an arithmetic number, because the mean of its divisors is an integer number (777278061).

Almost surely, 2^1554556121 is an apocalyptic number.

It is an amenable number.

1554556121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1554556121 is an equidigital number, since it uses as much as digits as its factorization.

1554556121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30000, while the sum is 35.

The square root of 1554556121 is about 39427.8597060505. The cubic root of 1554556121 is about 1158.4273479075.

The spelling of 1554556121 in words is "one billion, five hundred fifty-four million, five hundred fifty-six thousand, one hundred twenty-one".