61172779 has 4 divisors (see below), whose sum is σ = 62664840. Its totient is φ = 59680720.

The previous prime is 61172777. The next prime is 61172807. The reversal of 61172779 is 97727116.

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 61172779 - 2¹ = 61172777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61172777) 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, 745969 + ... + 746050.

It is an arithmetic number, because the mean of its divisors is an integer number (15666210).

Almost surely, 2^61172779 is an apocalyptic number.

61172779 is a deficient number, since it is larger than the sum of its proper divisors (1492061).

61172779 is a wasteful number, since it uses less digits than its factorization.

61172779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1492060.

The product of its digits is 37044, while the sum is 40.

The square root of 61172779 is about 7821.3028965768. The cubic root of 61172779 is about 394.0210313698.

The spelling of 61172779 in words is "sixty-one million, one hundred seventy-two thousand, seven hundred seventy-nine".