921072672 has 288 divisors, whose sum is σ = 2971528560. Its totient is φ = 268738560.

The previous prime is 921072643. The next prime is 921072673. The reversal of 921072672 is 276270129.

It can be written as a sum of positive squares in 8 ways, for example, as 308213136 + 612859536 = 17556^2 + 24756^2 .

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (921072673) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8450154 + ... + 8450262.

Almost surely, 2^921072672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 921072672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1485764280).

921072672 is an abundant number, since it is smaller than the sum of its proper divisors (2050455888).

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

921072672 is a wasteful number, since it uses less digits than its factorization.

921072672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 921072672 is about 30349.1790992771. The cubic root of 921072672 is about 972.9666753486.

The spelling of 921072672 in words is "nine hundred twenty-one million, seventy-two thousand, six hundred seventy-two".