61387500 has 72 divisors (see below), whose sum is σ = 179144784. Its totient is φ = 16360000.

The previous prime is 61387481. The next prime is 61387507. The reversal of 61387500 is 578316.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (61387507) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36682 + ... + 38318.

It is an arithmetic number, because the mean of its divisors is an integer number (2488122).

Almost surely, 2^61387500 is an apocalyptic number.

61387500 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61387500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89572392).

61387500 is an abundant number, since it is smaller than the sum of its proper divisors (117757284).

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

61387500 is a wasteful number, since it uses less digits than its factorization.

61387500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1669 (or 1647 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 61387500 is about 7835.0175494379. The cubic root of 61387500 is about 394.4815073875.

The spelling of 61387500 in words is "sixty-one million, three hundred eighty-seven thousand, five hundred".