981779820 has 48 divisors (see below), whose sum is σ = 3141696768. Its totient is φ = 224406720.

The previous prime is 981779797. The next prime is 981779839. The reversal of 981779820 is 28977189.

It is a super-2 number, since 2×981779820² = 1927783229918464800, which contains 22 as substring.

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, 1168366 + ... + 1169205.

It is an arithmetic number, because the mean of its divisors is an integer number (65452016).

Almost surely, 2^981779820 is an apocalyptic number.

It is an amenable number.

981779820 is an abundant number, since it is smaller than the sum of its proper divisors (2159916948).

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

981779820 is a wasteful number, since it uses less digits than its factorization.

981779820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2337590 (or 2337588 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 51.

The square root of 981779820 is about 31333.3659219689. The cubic root of 981779820 is about 993.8893425903.

The spelling of 981779820 in words is "nine hundred eighty-one million, seven hundred seventy-nine thousand, eight hundred twenty".