249072721920 has 672 divisors, whose sum is σ = 949511496960. Its totient is φ = 59894661120.

The previous prime is 249072721897. The next prime is 249072721939. The reversal of 249072721920 is 29127270942.

It is a happy number.

249072721920 is a `hidden beast` number, since 2 + 490 + 7 + 2 + 72 + 1 + 92 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 969154432 + ... + 969154688.

Almost surely, 2^249072721920 is an apocalyptic number.

249072721920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 249072721920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (474755748480).

249072721920 is an abundant number, since it is smaller than the sum of its proper divisors (700438775040).

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

249072721920 is a wasteful number, since it uses less digits than its factorization.

249072721920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544 (or 517 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The spelling of 249072721920 in words is "two hundred forty-nine billion, seventy-two million, seven hundred twenty-one thousand, nine hundred twenty".