61921161 has 27 divisors (see below), whose sum is σ = 93095847. Its totient is φ = 39659760.

The previous prime is 61921151. The next prime is 61921169. The reversal of 61921161 is 16112916.

The square root of 61921161 is 7869.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2013561 + 59907600 = 1419^2 + 7740^2 .

It is not a de Polignac number, because 61921161 - 2¹¹ = 61919113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61921169) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1015071 + ... + 1015131.

Almost surely, 2^61921161 is an apocalyptic number.

61921161 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

61921161 is the 7869-th square number.

61921161 is the 3935-th centered octagonal number.

It is an amenable number.

61921161 is a deficient number, since it is larger than the sum of its proper divisors (31174686).

61921161 is an equidigital number, since it uses as much as digits as its factorization.

61921161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214 (or 107 counting only the distinct ones).

The product of its digits is 648, while the sum is 27.

The cubic root of 61921161 is about 395.6213284027.

The spelling of 61921161 in words is "sixty-one million, nine hundred twenty-one thousand, one hundred sixty-one".