1550254991 has 2 divisors, whose sum is σ = 1550254992. Its totient is φ = 1550254990.

The previous prime is 1550254987. The next prime is 1550254997. The reversal of 1550254991 is 1994520551.

It is a weak prime.

It is an emirp because it is prime and its reverse (1994520551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1550254991 - 2² = 1550254987 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1550254997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775127495 + 775127496.

It is an arithmetic number, because the mean of its divisors is an integer number (775127496).

Almost surely, 2^1550254991 is an apocalyptic number.

1550254991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1550254991 is an equidigital number, since it uses as much as digits as its factorization.

1550254991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81000, while the sum is 41.

The square root of 1550254991 is about 39373.2776258213. The cubic root of 1550254991 is about 1157.3579860819.

The spelling of 1550254991 in words is "one billion, five hundred fifty million, two hundred fifty-four thousand, nine hundred ninety-one".