61810909924 has 9 divisors (see below), whose sum is σ = 108169962537. Its totient is φ = 30905206344.

The previous prime is 61810909819. The next prime is 61810909933. The reversal of 61810909924 is 42990901816.

It is a happy number.

The square root of 61810909924 is 248618.

It is a perfect power (a square), and thus also a powerful number.

61810909924 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 10861391524 + 50949518400 = 104218^2 + 225720^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 435082 + ... + 559390.

Almost surely, 2^61810909924 is an apocalyptic number.

61810909924 is the 248618-th square number.

It is an amenable number.

61810909924 is a deficient number, since it is larger than the sum of its proper divisors (46359052613).

61810909924 is an frugal number, since it uses more digits than its factorization.

61810909924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248622 (or 124311 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 49.

Multiplying 61810909924 by its sum of digits (49), we get a square (3028734586276 = 1740326²).

The spelling of 61810909924 in words is "sixty-one billion, eight hundred ten million, nine hundred nine thousand, nine hundred twenty-four".