1226721258620 has 288 divisors, whose sum is σ = 3089322016704. Its totient is φ = 406408273920.

The previous prime is 1226721258599. The next prime is 1226721258641. The reversal of 1226721258620 is 268521276221.

It is an interprime number because it is at equal distance from previous prime (1226721258599) and next prime (1226721258641).

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1255599572 + ... + 1255600548.

It is an arithmetic number, because the mean of its divisors is an integer number (10726812558).

Almost surely, 2^{1226721258620} is an apocalyptic number.

1226721258620 is a gapful number since it is divisible by the number (10) 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 1226721258620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1544661008352).

1226721258620 is an abundant number, since it is smaller than the sum of its proper divisors (1862600758084).

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

1226721258620 is a wasteful number, since it uses less digits than its factorization.

1226721258620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501 (or 1488 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 1226721258620 in words is "one trillion, two hundred twenty-six billion, seven hundred twenty-one million, two hundred fifty-eight thousand, six hundred twenty".