1212532561 has 4 divisors (see below), whose sum is σ = 1265251392. Its totient is φ = 1159813732.

The previous prime is 1212532553. The next prime is 1212532571. The reversal of 1212532561 is 1652352121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1652352121 = 7 ⋅236050303.

It is not a de Polignac number, because 1212532561 - 2³ = 1212532553 is a prime.

It is a super-2 number, since 2×1212532561² = 2940470422970437442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212532571) 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 in 3 ways as a sum of consecutive naturals, for example, 26359381 + ... + 26359426.

It is an arithmetic number, because the mean of its divisors is an integer number (316312848).

Almost surely, 2^1212532561 is an apocalyptic number.

It is an amenable number.

1212532561 is a deficient number, since it is larger than the sum of its proper divisors (52718831).

1212532561 is an equidigital number, since it uses as much as digits as its factorization.

1212532561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52718830.

The product of its digits is 3600, while the sum is 28.

The square root of 1212532561 is about 34821.4382385335. The cubic root of 1212532561 is about 1066.3451629470.

Adding to 1212532561 its reverse (1652352121), we get a palindrome (2864884682).

The spelling of 1212532561 in words is "one billion, two hundred twelve million, five hundred thirty-two thousand, five hundred sixty-one".