61945709 has 4 divisors (see below), whose sum is σ = 70795104. Its totient is φ = 53096316.

The previous prime is 61945703. The next prime is 61945727. The reversal of 61945709 is 90754916.

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 61945709 - 2¹⁶ = 61880173 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 (61945703) 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, 4424687 + ... + 4424700.

It is an arithmetic number, because the mean of its divisors is an integer number (17698776).

Almost surely, 2^61945709 is an apocalyptic number.

It is an amenable number.

61945709 is a deficient number, since it is larger than the sum of its proper divisors (8849395).

61945709 is an equidigital number, since it uses as much as digits as its factorization.

61945709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8849394.

The product of its (nonzero) digits is 68040, while the sum is 41.

The square root of 61945709 is about 7870.5596370271. The cubic root of 61945709 is about 395.6736014820.

The spelling of 61945709 in words is "sixty-one million, nine hundred forty-five thousand, seven hundred nine".