1553972191 has 2 divisors, whose sum is σ = 1553972192. Its totient is φ = 1553972190.

The previous prime is 1553972153. The next prime is 1553972197. The reversal of 1553972191 is 1912793551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1553972191 - 2²³ = 1545583583 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1553972197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 776986095 + 776986096.

It is an arithmetic number, because the mean of its divisors is an integer number (776986096).

Almost surely, 2^1553972191 is an apocalyptic number.

1553972191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1553972191 is an equidigital number, since it uses as much as digits as its factorization.

1553972191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 85050, while the sum is 43.

The square root of 1553972191 is about 39420.4539674520. The cubic root of 1553972191 is about 1158.2822850209.

The spelling of 1553972191 in words is "one billion, five hundred fifty-three million, nine hundred seventy-two thousand, one hundred ninety-one".