1555657243 has 12 divisors (see below), whose sum is σ = 1904887560. Its totient is φ = 1263239712.

The previous prime is 1555657241. The next prime is 1555657261. The reversal of 1555657243 is 3427565551.

It is not a de Polignac number, because 1555657243 - 2¹ = 1555657241 is a prime.

It is a super-2 number, since 2×1555657243² = 4840138915396722098, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1555657243.

It is not an unprimeable number, because it can be changed into a prime (1555657241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 834546 + ... + 836407.

It is an arithmetic number, because the mean of its divisors is an integer number (158740630).

Almost surely, 2^1555657243 is an apocalyptic number.

1555657243 is a deficient number, since it is larger than the sum of its proper divisors (349230317).

1555657243 is a wasteful number, since it uses less digits than its factorization.

1555657243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1670986 (or 1670979 counting only the distinct ones).

The product of its digits is 630000, while the sum is 43.

The square root of 1555657243 is about 39441.8209899087. The cubic root of 1555657243 is about 1158.7007954787.

The spelling of 1555657243 in words is "one billion, five hundred fifty-five million, six hundred fifty-seven thousand, two hundred forty-three".