61211553 has 16 divisors (see below), whose sum is σ = 88441920. Its totient is φ = 37433664.

The previous prime is 61211539. The next prime is 61211599. The reversal of 61211553 is 35511216.

It is not a de Polignac number, because 61211553 - 2⁴ = 61211537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61011553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1543 + ... + 11171.

It is an arithmetic number, because the mean of its divisors is an integer number (5527620).

Almost surely, 2^61211553 is an apocalyptic number.

It is an amenable number.

61211553 is a deficient number, since it is larger than the sum of its proper divisors (27230367).

61211553 is a wasteful number, since it uses less digits than its factorization.

61211553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9808.

The product of its digits is 900, while the sum is 24.

The square root of 61211553 is about 7823.7812469419. The cubic root of 61211553 is about 394.1042630781.

Adding to 61211553 its reverse (35511216), we get a palindrome (96722769).

The spelling of 61211553 in words is "sixty-one million, two hundred eleven thousand, five hundred fifty-three".