61811904 has 224 divisors, whose sum is σ = 211262976. Its totient is φ = 15482880.

The previous prime is 61811903. The next prime is 61811927. The reversal of 61811904 is 40911816.

61811904 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-2 number, since 2×61811904² = 7641422952210432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61811903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 546952 + ... + 547064.

Almost surely, 2^61811904 is an apocalyptic number.

61811904 is a gapful number since it is divisible by the number (64) 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 61811904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105631488).

61811904 is an abundant number, since it is smaller than the sum of its proper divisors (149451072).

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

61811904 is a wasteful number, since it uses less digits than its factorization.

61811904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 61811904 is about 7862.0546932720. The cubic root of 61811904 is about 395.3885062882.

The spelling of 61811904 in words is "sixty-one million, eight hundred eleven thousand, nine hundred four".