61139740 has 24 divisors (see below), whose sum is σ = 130818240. Its totient is φ = 23994048.

The previous prime is 61139731. The next prime is 61139747. The reversal of 61139740 is 4793116.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61139747) 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, 27780 + ... + 29899.

It is an arithmetic number, because the mean of its divisors is an integer number (5450760).

Almost surely, 2^61139740 is an apocalyptic number.

It is an amenable number.

61139740 is an abundant number, since it is smaller than the sum of its proper divisors (69678500).

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

61139740 is a wasteful number, since it uses less digits than its factorization.

61139740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57741 (or 57739 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 61139740 is about 7819.1904951855. The cubic root of 61139740 is about 393.9500825729.

The spelling of 61139740 in words is "sixty-one million, one hundred thirty-nine thousand, seven hundred forty".