61511957 has 4 divisors (see below), whose sum is σ = 66243660. Its totient is φ = 56780256.

The previous prime is 61511953. The next prime is 61511969. The reversal of 61511957 is 75911516.

It is a happy number.

61511957 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 28633201 + 32878756 = 5351^2 + 5734^2 .

It is not a de Polignac number, because 61511957 - 2² = 61511953 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61511951) 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, 2365832 + ... + 2365857.

It is an arithmetic number, because the mean of its divisors is an integer number (16560915).

Almost surely, 2^61511957 is an apocalyptic number.

It is an amenable number.

61511957 is a deficient number, since it is larger than the sum of its proper divisors (4731703).

61511957 is a wasteful number, since it uses less digits than its factorization.

61511957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4731702.

The product of its digits is 9450, while the sum is 35.

The square root of 61511957 is about 7842.9558841039. The cubic root of 61511957 is about 394.7479179935.

The spelling of 61511957 in words is "sixty-one million, five hundred eleven thousand, nine hundred fifty-seven".