1551550001 has 2 divisors, whose sum is σ = 1551550002. Its totient is φ = 1551550000.

The previous prime is 1551549997. The next prime is 1551550027. The reversal of 1551550001 is 1000551551.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1411955776 + 139594225 = 37576^2 + 11815^2 .

It is a cyclic number.

It is not a de Polignac number, because 1551550001 - 2² = 1551549997 is a prime.

It is not a weakly prime, because it can be changed into another prime (1551550501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775775000 + 775775001.

It is an arithmetic number, because the mean of its divisors is an integer number (775775001).

Almost surely, 2^1551550001 is an apocalyptic number.

It is an amenable number.

1551550001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1551550001 is an equidigital number, since it uses as much as digits as its factorization.

1551550001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 625, while the sum is 23.

The square root of 1551550001 is about 39389.7194836419. The cubic root of 1551550001 is about 1157.6801638372.

The spelling of 1551550001 in words is "one billion, five hundred fifty-one million, five hundred fifty thousand, one".