1085661553 has 2 divisors, whose sum is σ = 1085661554. Its totient is φ = 1085661552.

The previous prime is 1085661547. The next prime is 1085661557. The reversal of 1085661553 is 3551665801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 972940864 + 112720689 = 31192^2 + 10617^2 .

It is a cyclic number.

It is not a de Polignac number, because 1085661553 - 2⁹ = 1085661041 is a prime.

It is a super-2 number, since 2×1085661553² = 2357322015324743618, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1085661557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 542830776 + 542830777.

It is an arithmetic number, because the mean of its divisors is an integer number (542830777).

Almost surely, 2^1085661553 is an apocalyptic number.

It is an amenable number.

1085661553 is a deficient number, since it is larger than the sum of its proper divisors (1).

1085661553 is an equidigital number, since it uses as much as digits as its factorization.

1085661553 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108000, while the sum is 40.

The square root of 1085661553 is about 32949.3786436103. The cubic root of 1085661553 is about 1027.7752442702.

The spelling of 1085661553 in words is "one billion, eighty-five million, six hundred sixty-one thousand, five hundred fifty-three".