61142779 has 4 divisors (see below), whose sum is σ = 64360840. Its totient is φ = 57924720.

The previous prime is 61142747. The next prime is 61142789. The reversal of 61142779 is 97724116.

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 61142779 - 2⁵ = 61142747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61142789) 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, 1609002 + ... + 1609039.

It is an arithmetic number, because the mean of its divisors is an integer number (16090210).

Almost surely, 2^61142779 is an apocalyptic number.

61142779 is a deficient number, since it is larger than the sum of its proper divisors (3218061).

61142779 is a wasteful number, since it uses less digits than its factorization.

61142779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3218060.

The product of its digits is 21168, while the sum is 37.

The square root of 61142779 is about 7819.3848223502. The cubic root of 61142779 is about 393.9566096668.

The spelling of 61142779 in words is "sixty-one million, one hundred forty-two thousand, seven hundred seventy-nine".