20146679721 has 63 divisors (see below), whose sum is σ = 35184676653. Its totient is φ = 11497059000.

The previous prime is 20146679699. The next prime is 20146679741. The reversal of 20146679721 is 12797664102.

The square root of 20146679721 is 141939.

It is a perfect power (a square), and thus also a powerful number.

It is a tau number, because it is divible by the number of its divisors (63).

It is not a de Polignac number, because 20146679721 - 2¹³ = 20146671529 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20146679741) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 26826096 + ... + 26826846.

It is an arithmetic number, because the mean of its divisors is an integer number (558486931).

Almost surely, 2^20146679721 is an apocalyptic number.

20146679721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20146679721 is the 141939-th square number.

20146679721 is the 70970-th centered octagonal number.

It is an amenable number.

20146679721 is a deficient number, since it is larger than the sum of its proper divisors (15037996932).

20146679721 is an frugal number, since it uses more digits than its factorization.

20146679721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1534 (or 761 counting only the distinct ones).

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

The spelling of 20146679721 in words is "twenty billion, one hundred forty-six million, six hundred seventy-nine thousand, seven hundred twenty-one".