20122121987 has 16 divisors (see below), whose sum is σ = 23338015488. Its totient is φ = 17167344480.

The previous prime is 20122121843. The next prime is 20122121989. The reversal of 20122121987 is 78912122102.

It is not a de Polignac number, because 20122121987 - 2²⁰ = 20121073411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20122121989) 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, 736913 + ... + 763730.

It is an arithmetic number, because the mean of its divisors is an integer number (1458625968).

Almost surely, 2^20122121987 is an apocalyptic number.

20122121987 is a deficient number, since it is larger than the sum of its proper divisors (3215893501).

20122121987 is a wasteful number, since it uses less digits than its factorization.

20122121987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500730.

The product of its (nonzero) digits is 8064, while the sum is 35.

The spelling of 20122121987 in words is "twenty billion, one hundred twenty-two million, one hundred twenty-one thousand, nine hundred eighty-seven".