61543920 has 80 divisors (see below), whose sum is σ = 191594880. Its totient is φ = 16342272.

The previous prime is 61543877. The next prime is 61543943. The reversal of 61543920 is 2934516.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 82911 + ... + 83649.

It is an arithmetic number, because the mean of its divisors is an integer number (2394936).

Almost surely, 2^61543920 is an apocalyptic number.

61543920 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 61543920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95797440).

61543920 is an abundant number, since it is smaller than the sum of its proper divisors (130050960).

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

61543920 is a wasteful number, since it uses less digits than its factorization.

61543920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1102 (or 1096 counting only the distinct ones).

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

The square root of 61543920 is about 7844.9933078365. The cubic root of 61543920 is about 394.8162794608.

The spelling of 61543920 in words is "sixty-one million, five hundred forty-three thousand, nine hundred twenty".