61071820 has 24 divisors (see below), whose sum is σ = 135795744. Its totient is φ = 22991616.

The previous prime is 61071809. The next prime is 61071823. The reversal of 61071820 is 2817016.

It is a super-2 number, since 2×61071820² = 7459534396224800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61071823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89472 + ... + 90151.

It is an arithmetic number, because the mean of its divisors is an integer number (5658156).

Almost surely, 2^61071820 is an apocalyptic number.

It is an amenable number.

61071820 is an abundant number, since it is smaller than the sum of its proper divisors (74723924).

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

61071820 is a wasteful number, since it uses less digits than its factorization.

61071820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179649 (or 179647 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 61071820 is about 7814.8461277238. The cubic root of 61071820 is about 393.8041490996.

Adding to 61071820 its reverse (2817016), we get a palindrome (63888836).

The spelling of 61071820 in words is "sixty-one million, seventy-one thousand, eight hundred twenty".