61711540 has 24 divisors (see below), whose sum is σ = 141376032. Its totient is φ = 22440480.

The previous prime is 61711537. The next prime is 61711541. The reversal of 61711540 is 4511716.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61711541) 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, 140034 + ... + 140473.

It is an arithmetic number, because the mean of its divisors is an integer number (5890668).

Almost surely, 2^61711540 is an apocalyptic number.

It is an amenable number.

61711540 is an abundant number, since it is smaller than the sum of its proper divisors (79664492).

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

61711540 is a wasteful number, since it uses less digits than its factorization.

61711540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280527 (or 280525 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 61711540 is about 7855.6692903915. The cubic root of 61711540 is about 395.1743928974.

The spelling of 61711540 in words is "sixty-one million, seven hundred eleven thousand, five hundred forty".