2102121656 has 32 divisors (see below), whose sum is σ = 4071513600. Its totient is φ = 1016433120.

The previous prime is 2102121643. The next prime is 2102121667. The reversal of 2102121656 is 6561212012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 554375 + ... + 558153.

It is an arithmetic number, because the mean of its divisors is an integer number (127234800).

Almost surely, 2^2102121656 is an apocalyptic number.

It is an amenable number.

2102121656 is a deficient number, since it is larger than the sum of its proper divisors (1969391944).

2102121656 is a wasteful number, since it uses less digits than its factorization.

2102121656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6059 (or 6055 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 2102121656 is about 45848.9002703445. The cubic root of 2102121656 is about 1281.0102814944.

Adding to 2102121656 its reverse (6561212012), we get a palindrome (8663333668).

The spelling of 2102121656 in words is "two billion, one hundred two million, one hundred twenty-one thousand, six hundred fifty-six".