61921 has 4 divisors (see below), whose sum is σ = 65200. Its totient is φ = 58644.

The previous prime is 61909. The next prime is 61927. The reversal of 61921 is 12916.

61921 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61921 - 2⁹ = 61409 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 3259 = 61921 / (6 + 1 + 9 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61927) 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, 1611 + ... + 1648.

It is an arithmetic number, because the mean of its divisors is an integer number (16300).

2⁶¹⁹²¹ is an apocalyptic number.

It is an amenable number.

61921 is a deficient number, since it is larger than the sum of its proper divisors (3279).

61921 is a wasteful number, since it uses less digits than its factorization.

61921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3278.

The product of its digits is 108, while the sum is 19.

The square root of 61921 is about 248.8393055769. The cubic root of 61921 is about 39.5620985520.

The spelling of 61921 in words is "sixty-one thousand, nine hundred twenty-one".