61445761 has 4 divisors (see below), whose sum is σ = 66172372. Its totient is φ = 56719152.

The previous prime is 61445749. The next prime is 61445771. The reversal of 61445761 is 16754416.

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 16810000 + 44635761 = 4100^2 + 6681^2 .

It is a cyclic number.

It is not a de Polignac number, because 61445761 - 2⁵ = 61445729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61445711) 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, 2363286 + ... + 2363311.

It is an arithmetic number, because the mean of its divisors is an integer number (16543093).

Almost surely, 2^61445761 is an apocalyptic number.

It is an amenable number.

61445761 is a deficient number, since it is larger than the sum of its proper divisors (4726611).

61445761 is a wasteful number, since it uses less digits than its factorization.

61445761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4726610.

The product of its digits is 20160, while the sum is 34.

The square root of 61445761 is about 7838.7346555423. The cubic root of 61445761 is about 394.6062647086.

The spelling of 61445761 in words is "sixty-one million, four hundred forty-five thousand, seven hundred sixty-one".