61343440 has 20 divisors (see below), whose sum is σ = 142623684. Its totient is φ = 24537344.

The previous prime is 61343431. The next prime is 61343459. The reversal of 61343440 is 4434316.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10705984 + 50637456 = 3272^2 + 7116^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 383317 + ... + 383476.

Almost surely, 2^61343440 is an apocalyptic number.

It is an amenable number.

61343440 is an abundant number, since it is smaller than the sum of its proper divisors (81280244).

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

61343440 is a wasteful number, since it uses less digits than its factorization.

61343440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 766806 (or 766800 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 61343440 is about 7832.2053088514. The cubic root of 61343440 is about 394.3871069794.

Adding to 61343440 its reverse (4434316), we get a palindrome (65777756).

The spelling of 61343440 in words is "sixty-one million, three hundred forty-three thousand, four hundred forty".