61420921 has 2 divisors, whose sum is σ = 61420922. Its totient is φ = 61420920.

The previous prime is 61420873. The next prime is 61420937. The reversal of 61420921 is 12902416.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42758521 + 18662400 = 6539^2 + 4320^2 .

It is a cyclic number.

It is not a de Polignac number, because 61420921 - 2⁹ = 61420409 is a prime.

It is not a weakly prime, because it can be changed into another prime (61420981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30710460 + 30710461.

It is an arithmetic number, because the mean of its divisors is an integer number (30710461).

Almost surely, 2^61420921 is an apocalyptic number.

It is an amenable number.

61420921 is a deficient number, since it is larger than the sum of its proper divisors (1).

61420921 is an equidigital number, since it uses as much as digits as its factorization.

61420921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 61420921 is about 7837.1500559834. The cubic root of 61420921 is about 394.5530831677.

The spelling of 61420921 in words is "sixty-one million, four hundred twenty thousand, nine hundred twenty-one".