61434640 has 40 divisors (see below), whose sum is σ = 145883520. Its totient is φ = 24049536.

The previous prime is 61434631. The next prime is 61434643. The reversal of 61434640 is 4643416.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 61434599 and 61434608.

It is not an unprimeable number, because it can be changed into a prime (61434643) 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, 4410 + ... + 11929.

It is an arithmetic number, because the mean of its divisors is an integer number (3647088).

Almost surely, 2^61434640 is an apocalyptic number.

It is an amenable number.

61434640 is an abundant number, since it is smaller than the sum of its proper divisors (84448880).

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

61434640 is a wasteful number, since it uses less digits than its factorization.

61434640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16399 (or 16393 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 61434640 is about 7838.0252615056. The cubic root of 61434640 is about 394.5824568224.

It can be divided in two parts, 614346 and 40, that added together give a triangular number (614386 = T₁₁₀₈).

The spelling of 61434640 in words is "sixty-one million, four hundred thirty-four thousand, six hundred forty".