1205545531 has 4 divisors (see below), whose sum is σ = 1276459992. Its totient is φ = 1134631072.

The previous prime is 1205545513. The next prime is 1205545553. The reversal of 1205545531 is 1355455021.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1205545531 - 2⁷ = 1205545403 is a prime.

It is a super-2 number, since 2×1205545531² = 2906680054628143922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1205545493 and 1205545502.

It is not an unprimeable number, because it can be changed into a prime (1205545571) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35457205 + ... + 35457238.

It is an arithmetic number, because the mean of its divisors is an integer number (319114998).

Almost surely, 2^1205545531 is an apocalyptic number.

1205545531 is a deficient number, since it is larger than the sum of its proper divisors (70914461).

1205545531 is an equidigital number, since it uses as much as digits as its factorization.

1205545531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70914460.

The product of its (nonzero) digits is 15000, while the sum is 31.

The square root of 1205545531 is about 34720.9667348131. The cubic root of 1205545531 is about 1064.2930001650.

The spelling of 1205545531 in words is "one billion, two hundred five million, five hundred forty-five thousand, five hundred thirty-one".