61681020 has 24 divisors (see below), whose sum is σ = 172707024. Its totient is φ = 16448256.

The previous prime is 61680989. The next prime is 61681027. The reversal of 61681020 is 2018616.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61681027) 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, 513949 + ... + 514068.

It is an arithmetic number, because the mean of its divisors is an integer number (7196126).

Almost surely, 2^61681020 is an apocalyptic number.

61681020 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61681020 is an abundant number, since it is smaller than the sum of its proper divisors (111026004).

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

61681020 is a wasteful number, since it uses less digits than its factorization.

61681020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1028029 (or 1028027 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 61681020 is about 7853.7265040234. The cubic root of 61681020 is about 395.1092364654.

Adding to 61681020 its reverse (2018616), we get a palindrome (63699636).

The spelling of 61681020 in words is "sixty-one million, six hundred eighty-one thousand, twenty".