61444139 has 4 divisors (see below), whose sum is σ = 63426240. Its totient is φ = 59462040.

The previous prime is 61444121. The next prime is 61444189. The reversal of 61444139 is 93144416.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61444139 - 2⁸ = 61443883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61444189) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 991004 + ... + 991065.

It is an arithmetic number, because the mean of its divisors is an integer number (15856560).

Almost surely, 2^61444139 is an apocalyptic number.

61444139 is a deficient number, since it is larger than the sum of its proper divisors (1982101).

61444139 is a wasteful number, since it uses less digits than its factorization.

61444139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1982100.

The product of its digits is 10368, while the sum is 32.

The square root of 61444139 is about 7838.6311942839. The cubic root of 61444139 is about 394.6027925027.

The spelling of 61444139 in words is "sixty-one million, four hundred forty-four thousand, one hundred thirty-nine".