61720245 has 32 divisors (see below), whose sum is σ = 110183040. Its totient is φ = 32780160.

The previous prime is 61720237. The next prime is 61720271. The reversal of 61720245 is 54202716.

61720245 is a `hidden beast` number, since 617 + 2 + 0 + 2 + 45 = 666.

It is not a de Polignac number, because 61720245 - 2³ = 61720237 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37122 + ... + 38748.

It is an arithmetic number, because the mean of its divisors is an integer number (3443220).

Almost surely, 2^61720245 is an apocalyptic number.

It is an amenable number.

61720245 is a deficient number, since it is larger than the sum of its proper divisors (48462795).

61720245 is a wasteful number, since it uses less digits than its factorization.

61720245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1922 (or 1916 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 61720245 is about 7856.2233293103. The cubic root of 61720245 is about 395.1929730600.

The spelling of 61720245 in words is "sixty-one million, seven hundred twenty thousand, two hundred forty-five".