61547993 has 4 divisors (see below), whose sum is σ = 66282468. Its totient is φ = 56813520.

The previous prime is 61547951. The next prime is 61548001. The reversal of 61547993 is 39974516.

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 8082649 + 53465344 = 2843^2 + 7312^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61547993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61547933) 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, 2367218 + ... + 2367243.

It is an arithmetic number, because the mean of its divisors is an integer number (16570617).

Almost surely, 2^61547993 is an apocalyptic number.

It is an amenable number.

61547993 is a deficient number, since it is larger than the sum of its proper divisors (4734475).

61547993 is a wasteful number, since it uses less digits than its factorization.

61547993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4734474.

The product of its digits is 204120, while the sum is 44.

The square root of 61547993 is about 7845.2528958600. The cubic root of 61547993 is about 394.8249889658.

The spelling of 61547993 in words is "sixty-one million, five hundred forty-seven thousand, nine hundred ninety-three".