61420640 has 48 divisors (see below), whose sum is σ = 147864528. Its totient is φ = 24101376.

The previous prime is 61420613. The next prime is 61420657. The reversal of 61420640 is 4602416.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4859 + ... + 12101.

It is an arithmetic number, because the mean of its divisors is an integer number (3080511).

Almost surely, 2^61420640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61420640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73932264).

61420640 is an abundant number, since it is smaller than the sum of its proper divisors (86443888).

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

61420640 is a wasteful number, since it uses less digits than its factorization.

61420640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7311 (or 7303 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 61420640 is about 7837.1321285276. The cubic root of 61420640 is about 394.5524814748.

The spelling of 61420640 in words is "sixty-one million, four hundred twenty thousand, six hundred forty".