61806520 has 32 divisors (see below), whose sum is σ = 145113120. Its totient is φ = 23647360.

The previous prime is 61806463. The next prime is 61806527. The reversal of 61806520 is 2560816.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61806527) 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, 32671 + ... + 34510.

It is an arithmetic number, because the mean of its divisors is an integer number (4534785).

Almost surely, 2^61806520 is an apocalyptic number.

It is an amenable number.

61806520 is an abundant number, since it is smaller than the sum of its proper divisors (83306600).

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

61806520 is a wasteful number, since it uses less digits than its factorization.

61806520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67215 (or 67211 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 61806520 is about 7861.7122816852. The cubic root of 61806520 is about 395.3770261180.

It can be divided in two parts, 61806 and 520, that added together give a palindrome (62326).

The spelling of 61806520 in words is "sixty-one million, eight hundred six thousand, five hundred twenty".