2123951912121 has 32 divisors (see below), whose sum is σ = 3132925221888. Its totient is φ = 1271428704000.

The previous prime is 2123951912113. The next prime is 2123951912233. The reversal of 2123951912121 is 1212191593212.

It is not a de Polignac number, because 2123951912121 - 2³ = 2123951912113 is a prime.

It is a super-2 number, since 2×2123951912121² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 2123951912121.

It is not an unprimeable number, because it can be changed into a prime (2123951912021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6177496 + ... + 6512246.

It is an arithmetic number, because the mean of its divisors is an integer number (97903913184).

Almost surely, 2^{2123951912121} is an apocalyptic number.

It is an amenable number.

2123951912121 is a deficient number, since it is larger than the sum of its proper divisors (1008973309767).

2123951912121 is a wasteful number, since it uses less digits than its factorization.

2123951912121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339201.

The product of its digits is 19440, while the sum is 39.

The spelling of 2123951912121 in words is "two trillion, one hundred twenty-three billion, nine hundred fifty-one million, nine hundred twelve thousand, one hundred twenty-one".