61865280 has 84 divisors (see below), whose sum is σ = 212800692. Its totient is φ = 16496640.

The previous prime is 61865267. The next prime is 61865291. The reversal of 61865280 is 8256816.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 33732864 + 28132416 = 5808^2 + 5304^2 .

It is a super-3 number, since 3×61865280³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7861 + ... + 13620.

Almost surely, 2^61865280 is an apocalyptic number.

61865280 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61865280 is an abundant number, since it is smaller than the sum of its proper divisors (150935412).

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

61865280 is a wasteful number, since it uses less digits than its factorization.

61865280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21504 (or 21491 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 61865280 is about 7865.4484932520. The cubic root of 61865280 is about 395.5022825664.

The spelling of 61865280 in words is "sixty-one million, eight hundred sixty-five thousand, two hundred eighty".