61881000 has 64 divisors (see below), whose sum is σ = 193078080. Its totient is φ = 16500800.

The previous prime is 61880981. The next prime is 61881047. The reversal of 61881000 is 18816.

It is a super-2 number, since 2×61881000² = 7658516322000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

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, 7314 + ... + 13313.

It is an arithmetic number, because the mean of its divisors is an integer number (3016845).

Almost surely, 2^61881000 is an apocalyptic number.

61881000 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61881000 is an abundant number, since it is smaller than the sum of its proper divisors (131197080).

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

61881000 is a wasteful number, since it uses less digits than its factorization.

61881000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20651 (or 20637 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 24.

The square root of 61881000 is about 7866.4477370666. The cubic root of 61881000 is about 395.5357788417.

Adding to 61881000 its reverse (18816), we get a palindrome (61899816).

It can be divided in two parts, 618 and 81000, that added together give a palindrome (81618).

The spelling of 61881000 in words is "sixty-one million, eight hundred eighty-one thousand".