1655551 has 2 divisors, whose sum is σ = 1655552. Its totient is φ = 1655550.

The previous prime is 1655531. The next prime is 1655557. The reversal of 1655551 is 1555561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1655551 - 2⁹ = 1655039 is a prime.

It is a super-2 number, since 2×1655551² = 5481698227202, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1655557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 827775 + 827776.

It is an arithmetic number, because the mean of its divisors is an integer number (827776).

2^1655551 is an apocalyptic number.

1655551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1655551 is an equidigital number, since it uses as much as digits as its factorization.

1655551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3750, while the sum is 28.

The square root of 1655551 is about 1286.6821674369. The cubic root of 1655551 is about 118.2989403895.

The spelling of 1655551 in words is "one million, six hundred fifty-five thousand, five hundred fifty-one".