101978644 has 12 divisors (see below), whose sum is σ = 182815668. Its totient is φ = 49745600.

The previous prime is 101978633. The next prime is 101978647. The reversal of 101978644 is 446879101.

It can be written as a sum of positive squares in 2 ways, for example, as 10048900 + 91929744 = 3170^2 + 9588^2 .

It is a junction number, because it is equal to n+sod(n) for n = 101978597 and 101978606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101978647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 310747 + ... + 311074.

It is an arithmetic number, because the mean of its divisors is an integer number (15234639).

Almost surely, 2^101978644 is an apocalyptic number.

It is an amenable number.

101978644 is a deficient number, since it is larger than the sum of its proper divisors (80837024).

101978644 is a wasteful number, since it uses less digits than its factorization.

101978644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 621866 (or 621864 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 101978644 is about 10098.4476034686. The cubic root of 101978644 is about 467.2002619803.

The spelling of 101978644 in words is "one hundred one million, nine hundred seventy-eight thousand, six hundred forty-four".