1720661251950 has 72 divisors (see below), whose sum is σ = 4623716516328. Its totient is φ = 458756322240.

The previous prime is 1720661251949. The next prime is 1720661251961. The reversal of 1720661251950 is 591521660271.

It is a happy number.

1720661251950 is a `hidden beast` number, since 1 + 7 + 20 + 6 + 61 + 2 + 519 + 50 = 666.

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1720661251896 and 1720661251905.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2041357 + ... + 2758343.

It is an arithmetic number, because the mean of its divisors is an integer number (64218284949).

Almost surely, 2^{1720661251950} is an apocalyptic number.

1720661251950 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1720661251950 is an abundant number, since it is smaller than the sum of its proper divisors (2903055264378).

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

1720661251950 is a wasteful number, since it uses less digits than its factorization.

1720661251950 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722338 (or 722330 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 45.

The spelling of 1720661251950 in words is "one trillion, seven hundred twenty billion, six hundred sixty-one million, two hundred fifty-one thousand, nine hundred fifty".