20670755021 has 16 divisors (see below), whose sum is σ = 23720366976. Its totient is φ = 17645449536.

The previous prime is 20670754997. The next prime is 20670755023. The reversal of 20670755021 is 12055707602.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20670755021 - 2¹⁸ = 20670492877 is a prime.

It is a super-2 number, since 2×20670755021² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20670755023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1875890 + ... + 1886876.

It is an arithmetic number, because the mean of its divisors is an integer number (1482522936).

Almost surely, 2^20670755021 is an apocalyptic number.

It is an amenable number.

20670755021 is a deficient number, since it is larger than the sum of its proper divisors (3049611955).

20670755021 is a wasteful number, since it uses less digits than its factorization.

20670755021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12068.

The product of its (nonzero) digits is 29400, while the sum is 35.

The spelling of 20670755021 in words is "twenty billion, six hundred seventy million, seven hundred fifty-five thousand, twenty-one".