61506660 has 24 divisors (see below), whose sum is σ = 172218816. Its totient is φ = 16401760.

The previous prime is 61506619. The next prime is 61506673. The reversal of 61506660 is 6660516.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 512496 + ... + 512615.

It is an arithmetic number, because the mean of its divisors is an integer number (7175784).

Almost surely, 2^61506660 is an apocalyptic number.

61506660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61506660 is an abundant number, since it is smaller than the sum of its proper divisors (110712156).

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

61506660 is a wasteful number, since it uses less digits than its factorization.

61506660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1025123 (or 1025121 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 61506660 is about 7842.6181852746. The cubic root of 61506660 is about 394.7365866478.

The spelling of 61506660 in words is "sixty-one million, five hundred six thousand, six hundred sixty".