61215020 has 24 divisors (see below), whose sum is σ = 132027504. Its totient is φ = 23823936.

The previous prime is 61214971. The next prime is 61215023. The reversal of 61215020 is 2051216.

It is a self number, because there is not a number n which added to its sum of digits gives 61215020.

It is not an unprimeable number, because it can be changed into a prime (61215023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40622 + ... + 42101.

It is an arithmetic number, because the mean of its divisors is an integer number (5501146).

Almost surely, 2^61215020 is an apocalyptic number.

It is an amenable number.

61215020 is an abundant number, since it is smaller than the sum of its proper divisors (70812484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61215020 is a wasteful number, since it uses less digits than its factorization.

61215020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82769 (or 82767 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 61215020 is about 7824.0028118604. The cubic root of 61215020 is about 394.1117035782. Note that the first 3 decimals are identical.

Adding to 61215020 its reverse (2051216), we get a palindrome (63266236).

The spelling of 61215020 in words is "sixty-one million, two hundred fifteen thousand, twenty".