61439663 has 4 divisors (see below), whose sum is σ = 61491528. Its totient is φ = 61387800.

The previous prime is 61439659. The next prime is 61439681. The reversal of 61439663 is 36693416.

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

It is a cyclic number.

It is not a de Polignac number, because 61439663 - 2² = 61439659 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 (61439633) 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, 24113 + ... + 26538.

It is an arithmetic number, because the mean of its divisors is an integer number (15372882).

Almost surely, 2^61439663 is an apocalyptic number.

61439663 is a deficient number, since it is larger than the sum of its proper divisors (51865).

61439663 is a wasteful number, since it uses less digits than its factorization.

61439663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51864.

The product of its digits is 69984, while the sum is 38.

The square root of 61439663 is about 7838.3456800526. The cubic root of 61439663 is about 394.5932104389.

The spelling of 61439663 in words is "sixty-one million, four hundred thirty-nine thousand, six hundred sixty-three".