61981090 has 32 divisors (see below), whose sum is σ = 120185856. Its totient is φ = 22946880.

The previous prime is 61981081. The next prime is 61981111. The reversal of 61981090 is 9018916.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2784 + ... + 11476.

It is an arithmetic number, because the mean of its divisors is an integer number (3755808).

Almost surely, 2^61981090 is an apocalyptic number.

61981090 is a deficient number, since it is larger than the sum of its proper divisors (58204766).

61981090 is a wasteful number, since it uses less digits than its factorization.

61981090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8754.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 61981090 is about 7872.8069962371. The cubic root of 61981090 is about 395.7489183117.

The spelling of 61981090 in words is "sixty-one million, nine hundred eighty-one thousand, ninety".