61605090 has 64 divisors (see below), whose sum is σ = 166320000. Its totient is φ = 16224192.

The previous prime is 61605031. The next prime is 61605101. The reversal of 61605090 is 9050616.

It is a super-2 number, since 2×61605090² = 7590374227816200, which contains 22 as substring.

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

It is a Curzon number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 21036 + ... + 23784.

It is an arithmetic number, because the mean of its divisors is an integer number (2598750).

Almost surely, 2^61605090 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61605090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83160000).

61605090 is an abundant number, since it is smaller than the sum of its proper divisors (104714910).

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

61605090 is a wasteful number, since it uses less digits than its factorization.

61605090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2848 (or 2842 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 61605090 is about 7848.8910044668. The cubic root of 61605090 is about 394.9470419842.

The spelling of 61605090 in words is "sixty-one million, six hundred five thousand, ninety".