61005657 has 4 divisors (see below), whose sum is σ = 81340880. Its totient is φ = 40670436.

The previous prime is 61005643. The next prime is 61005667. The reversal of 61005657 is 75650016.

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.

It is not a de Polignac number, because 61005657 - 2⁴ = 61005641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61005667) 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, 10167607 + ... + 10167612.

It is an arithmetic number, because the mean of its divisors is an integer number (20335220).

Almost surely, 2^61005657 is an apocalyptic number.

It is an amenable number.

61005657 is a deficient number, since it is larger than the sum of its proper divisors (20335223).

61005657 is a wasteful number, since it uses less digits than its factorization.

61005657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20335222.

The product of its (nonzero) digits is 6300, while the sum is 30.

The square root of 61005657 is about 7810.6118198256. The cubic root of 61005657 is about 393.6618866579.

The spelling of 61005657 in words is "sixty-one million, five thousand, six hundred fifty-seven".