61405140 has 24 divisors (see below), whose sum is σ = 171934560. Its totient is φ = 16374688.

The previous prime is 61405133. The next prime is 61405153. The reversal of 61405140 is 4150416.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 511650 + ... + 511769.

It is an arithmetic number, because the mean of its divisors is an integer number (7163940).

Almost surely, 2^61405140 is an apocalyptic number.

61405140 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61405140 is an abundant number, since it is smaller than the sum of its proper divisors (110529420).

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

61405140 is a wasteful number, since it uses less digits than its factorization.

61405140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1023431 (or 1023429 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 61405140 is about 7836.1431839905. The cubic root of 61405140 is about 394.5192891691.

Adding to 61405140 its reverse (4150416), we get a palindrome (65555556).

The spelling of 61405140 in words is "sixty-one million, four hundred five thousand, one hundred forty".