61721077 has 16 divisors (see below), whose sum is σ = 70087680. Its totient is φ = 53838400.

The previous prime is 61721071. The next prime is 61721123. The reversal of 61721077 is 77012716.

It is not a de Polignac number, because 61721077 - 2¹¹ = 61719029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61721071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60423 + ... + 61435.

It is an arithmetic number, because the mean of its divisors is an integer number (4380480).

Almost surely, 2^61721077 is an apocalyptic number.

It is an amenable number.

61721077 is a deficient number, since it is larger than the sum of its proper divisors (8366603).

61721077 is a wasteful number, since it uses less digits than its factorization.

61721077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1244.

The product of its (nonzero) digits is 4116, while the sum is 31.

The square root of 61721077 is about 7856.2762807834. The cubic root of 61721077 is about 395.1947488095.

The spelling of 61721077 in words is "sixty-one million, seven hundred twenty-one thousand, seventy-seven".