2157208741972 has 6 divisors (see below), whose sum is σ = 3775115298458. Its totient is φ = 1078604370984.

The previous prime is 2157208741951. The next prime is 2157208741981. The reversal of 2157208741972 is 2791478027512.

It can be written as a sum of positive squares in only one way, i.e., 2116431401616 + 40777340356 = 1454796^2 + 201934^2 .

It is a super-3 number, since 3×2157208741972³ (a number of 38 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 269651092743 + ... + 269651092750.

Almost surely, 2^{2157208741972} is an apocalyptic number.

It is an amenable number.

2157208741972 is a deficient number, since it is larger than the sum of its proper divisors (1617906556486).

2157208741972 is a wasteful number, since it uses less digits than its factorization.

2157208741972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539302185497 (or 539302185495 counting only the distinct ones).

The product of its (nonzero) digits is 3951360, while the sum is 55.

The spelling of 2157208741972 in words is "two trillion, one hundred fifty-seven billion, two hundred eight million, seven hundred forty-one thousand, nine hundred seventy-two".