61281090 has 192 divisors, whose sum is σ = 189734400. Its totient is φ = 14017536.

The previous prime is 61281071. The next prime is 61281119. The reversal of 61281090 is 9018216.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 775671 + ... + 775749.

It is an arithmetic number, because the mean of its divisors is an integer number (988200).

Almost surely, 2^61281090 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61281090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94867200).

61281090 is an abundant number, since it is smaller than the sum of its proper divisors (128453310).

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

61281090 is a wasteful number, since it uses less digits than its factorization.

61281090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 61281090 is about 7828.2239365005. The cubic root of 61281090 is about 394.2534422006.

The spelling of 61281090 in words is "sixty-one million, two hundred eighty-one thousand, ninety".