61688028 has 24 divisors (see below), whose sum is σ = 147830032. Its totient is φ = 20006784.

The previous prime is 61688027. The next prime is 61688059. The reversal of 61688028 is 82088616.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61688021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69025 + ... + 69912.

Almost surely, 2^61688028 is an apocalyptic number.

It is an amenable number.

61688028 is an abundant number, since it is smaller than the sum of its proper divisors (86142004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61688028 is a wasteful number, since it uses less digits than its factorization.

61688028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138981 (or 138979 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 39.

The square root of 61688028 is about 7854.1726489809. The cubic root of 61688028 is about 395.1241995809.

It can be divided in two parts, 6168 and 8028, that added together give a triangular number (14196 = T₁₆₈).

The spelling of 61688028 in words is "sixty-one million, six hundred eighty-eight thousand, twenty-eight".