211521757942 has 12 divisors (see below), whose sum is σ = 348748683948. Its totient is φ = 96146253500.

The previous prime is 211521757927. The next prime is 211521757949. The reversal of 211521757942 is 249757125112.

It is a junction number, because it is equal to n+sod(n) for n = 211521757892 and 211521757901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211521757949) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 437028184 + ... + 437028667.

It is an arithmetic number, because the mean of its divisors is an integer number (29062390329).

Almost surely, 2^211521757942 is an apocalyptic number.

211521757942 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

211521757942 is a deficient number, since it is larger than the sum of its proper divisors (137226926006).

211521757942 is a wasteful number, since it uses less digits than its factorization.

211521757942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 874056875 (or 874056864 counting only the distinct ones).

The product of its digits is 352800, while the sum is 46.

The spelling of 211521757942 in words is "two hundred eleven billion, five hundred twenty-one million, seven hundred fifty-seven thousand, nine hundred forty-two".